CIS Amazon Web Services Foundations Benchmark v3.0.0
The CIS Amazon Web Services Foundations Benchmark provides prescriptive guidance for configuring security options for a subset of Amazon Web Services with an emphasis on foundational, testable, and architecture agnostic settings.
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1 Identity and Access Management2223
1.1Maintain current contact details1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
Ensure contact email and telephone details for AWS accounts are current and map to more than one individual in your organization. An AWS account supports a number of contact details, and AWS will use these to contact the account owner if activity judged to be in breach of Acceptable Use Policy or indicative of likely security compromise is observed by the AWS Abuse team. Contact details should not be for a single individual, as circumstances may arise where that individual is unavailable. Email contact details should point to a mail alias which forwards email to multiple individuals within the organization; where feasible, phone contact details should point to a PABX hunt group or other call-forwarding system.
- Audit Procedure
This activity can only be performed via the AWS Console, with a user who has permission to read and write Billing information (aws-portal:*Billing ) 1. Sign in to the AWS Management Console and open the Billing and Cost Management console at https://console.aws.amazon.com/billing/home#/. 2. On the navigation bar, choose your account name, and then choose Account. 3. On the Account Settings page, review and verify the current details. 4. Under Contact Information, review and verify the current details.
- Assessment Status
Manual
- Rationale Statement
If an AWS account is observed to be behaving in a prohibited or suspicious manner, AWS will attempt to contact the account owner by email and phone using the contact details listed. If this is unsuccessful and the account behavior needs urgent mitigation, proactive measures may be taken, including throttling of traffic between the account exhibiting suspicious behavior and the AWS API endpoints and the Internet. This will result in impaired service to and from the account in question, so it is in both the customers' and AWS' best interests that prompt contact can be established. This is best achieved by setting AWS account contact details to point to resources which have multiple individuals as recipients, such as email aliases and PABX hunt groups.
- Remediation Procedure
This activity can only be performed via the AWS Console, with a user who has permission to read and write Billing information (aws-portal:*Billing ). 1. Sign in to the AWS Management Console and open the Billing and Cost Management console at https://console.aws.amazon.com/billing/home#/. 2. On the navigation bar, choose your account name, and then choose Account. 3. On the Account Settings page, next to Account Settings, choose Edit. 4. Next to the field that you need to update, choose Edit. 5. After you have entered your changes, choose Save changes. 6. After you have made your changes, choose Done. 7. To edit your contact information, under Contact Information, choose Edit. 8. For the fields that you want to change, type your updated information, and then choose Update.
1.2Ensure security contact information is registered1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
AWS provides customers with the option of specifying the contact information for account's security team. It is recommended that this information be provided.
- Audit Procedure
Perform the following to determine if security contact information is present: From Console: 1. Click on your account name at the top right corner of the console 2. From the drop-down menu Click
My Account3. Scroll down to theAlternate Contactssection 4. Ensure contact information is specified in theSecuritysection- Assessment Status
Manual
- Rationale Statement
Specifying security-specific contact information will help ensure that security advisories sent by AWS reach the team in your organization that is best equipped to respond to them.
- Remediation Procedure
Perform the following to establish security contact information: From Console: 1. Click on your account name at the top right corner of the console. 2. From the drop-down menu Click
My Account3. Scroll down to theAlternate Contactssection 4. Enter contact information in theSecuritysection Note: Consider specifying an internal email distribution list to ensure emails are regularly monitored by more than one individual.
1.3Ensure security questions are registered in the AWS account1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
The AWS support portal allows account owners to establish security questions that can be used to authenticate individuals calling AWS customer service for support. It is recommended that security questions be established.
- Audit Procedure
From Console: 1. Login to the AWS account as the 'root' user 2. On the top right you will see the <Root_Account_Name> 3. Click on the <Root_Account_Name> 4. From the drop-down menu Click
My Account5. In theConfigure Security Challenge Questionssection on thePersonal Informationpage, configure three security challenge questions. 6. ClickSave questions.- Assessment Status
Manual
- Rationale Statement
When creating a new AWS account, a default super user is automatically created. This account is referred to as the 'root user' or 'root' account. It is recommended that the use of this account be limited and highly controlled. During events in which the 'root' password is no longer accessible or the MFA token associated with 'root' is lost/destroyed it is possible, through authentication using secret questions and associated answers, to recover 'root' user login access.
- Remediation Procedure
From Console: 1. Login to the AWS Account as the 'root' user 2. Click on the <Root_Account_Name> from the top right of the console 3. From the drop-down menu Click My Account 4. Scroll down to the
Configure Security Questionssection 5. Click onEdit6. Click on eachQuestion- From the drop-down select an appropriate question - Click on theAnswersection - Enter an appropriate answer - Follow process for all 3 questions 7. ClickUpdatewhen complete 8. Save Questions and Answers and place in a secure physical location
1.4Ensure no 'root' user account access key exists1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
The 'root' user account is the most privileged user in an AWS account. AWS Access Keys provide programmatic access to a given AWS account. It is recommended that all access keys associated with the 'root' user account be removed.
- Audit Procedure
Perform the following to determine if the 'root' user account has access keys: From Console: 1. Login to the AWS Management Console 2. Click
Services3. ClickIAM4. Click onCredential Report5. This will download a.csvfile which contains credential usage for all IAM users within an AWS Account - open this file 6. For the<root_account>user, ensure theaccess_key_1_activeandaccess_key_2_activefields are set toFALSE. From Command Line: Run the following command:aws iam get-account-summary | grep "AccountAccessKeysPresent"If no 'root' access keys exist the output will show "AccountAccessKeysPresent": 0,. If the output shows a "1" than 'root' keys exist, refer to the remediation procedure below.- Assessment Status
Automated
- Rationale Statement
Removing access keys associated with the 'root' user account limits vectors by which the account can be compromised. Additionally, removing the 'root' access keys encourages the creation and use of role based accounts that are least privileged.
- Remediation Procedure
Perform the following to delete or disable active 'root' user access keys From Console: 1. Sign in to the AWS Management Console as 'root' and open the IAM console at https://console.aws.amazon.com/iam/. 2. Click on <Root_Account_Name> at the top right and select
My Security Credentialsfrom the drop down list 3. On the pop out screen Click onContinue to Security Credentials4. Click onAccess Keys(Access Key ID and Secret Access Key) 5. Under theStatuscolumn if there are any Keys which are Active - Click onMake Inactive- (Temporarily disable Key - may be needed again) - ClickDelete- (Deleted keys cannot be recovered)- Additional Information
IAM User account "root" for us-gov cloud regions is not enabled by default. However, on request to AWS support enables 'root' access only through access-keys (CLI, API methods) for us-gov cloud region.
1.5Ensure MFA is enabled for the 'root' user account1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
The 'root' user account is the most privileged user in an AWS account. Multi-factor Authentication (MFA) adds an extra layer of protection on top of a username and password. With MFA enabled, when a user signs in to an AWS website, they will be prompted for their username and password as well as for an authentication code from their AWS MFA device. Note: When virtual MFA is used for 'root' accounts, it is recommended that the device used is NOT a personal device, but rather a dedicated mobile device (tablet or phone) that is managed to be kept charged and secured independent of any individual personal devices. ("non-personal virtual MFA") This lessens the risks of losing access to the MFA due to device loss, device trade-in or if the individual owning the device is no longer employed at the company.
- Audit Procedure
Perform the following to determine if the 'root' user account has MFA setup: From Console: 1. Login to the AWS Management Console 2. Click
Services3. ClickIAM4. Click onCredential Report5. This will download a.csvfile which contains credential usage for all IAM users within an AWS Account - open this file 6. For the<root_account>user, ensure themfa_activefield is set toTRUE. From Command Line: 1. Run the following command:aws iam get-account-summary | grep "AccountMFAEnabled"2. Ensure the AccountMFAEnabled property is set to 1- Assessment Status
Automated
- Rationale Statement
Enabling MFA provides increased security for console access as it requires the authenticating principal to possess a device that emits a time-sensitive key and have knowledge of a credential.
- Remediation Procedure
Perform the following to establish MFA for the 'root' user account: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/iam/. Note: to manage MFA devices for the 'root' AWS account, you must use your 'root' account credentials to sign in to AWS. You cannot manage MFA devices for the 'root' account using other credentials. 2. Choose
Dashboard, and underSecurity Status, expandActivate MFAon your root account. 3. ChooseActivate MFA4. In the wizard, chooseA virtual MFAdevice and then chooseNext Step. 5. IAM generates and displays configuration information for the virtual MFA device, including a QR code graphic. The graphic is a representation of the 'secret configuration key' that is available for manual entry on devices that do not support QR codes. 6. Open your virtual MFA application. (For a list of apps that you can use for hosting virtual MFA devices, see Virtual MFA Applications.) If the virtual MFA application supports multiple accounts (multiple virtual MFA devices), choose the option to create a new account (a new virtual MFA device). 7. Determine whether the MFA app supports QR codes, and then do one of the following: - Use the app to scan the QR code. For example, you might choose the camera icon or choose an option similar to Scan code, and then use the device's camera to scan the code. - In the Manage MFA Device wizard, choose Show secret key for manual configuration, and then type the secret configuration key into your MFA application. When you are finished, the virtual MFA device starts generating one-time passwords. In the Manage MFA Device wizard, in the Authentication Code 1 box, type the one-time password that currently appears in the virtual MFA device. Wait up to 30 seconds for the device to generate a new one-time password. Then type the second one-time password into the Authentication Code 2 box. Choose Assign Virtual MFA.- Additional Information
IAM User account "root" for us-gov cloud regions does not have console access. This recommendation is not applicable for us-gov cloud regions.
1.6Ensure hardware MFA is enabled for the 'root' user account1
Attributes
- Profile
Level 2
- Section
1 Identity and Access Management
- Description
The 'root' user account is the most privileged user in an AWS account. MFA adds an extra layer of protection on top of a user name and password. With MFA enabled, when a user signs in to an AWS website, they will be prompted for their user name and password as well as for an authentication code from their AWS MFA device. For Level 2, it is recommended that the 'root' user account be protected with a hardware MFA.
- Audit Procedure
Perform the following to determine if the 'root' user account has a hardware MFA setup: 1. Run the following command to determine if the 'root' account has MFA setup:
aws iam get-account-summary | grep "AccountMFAEnabled"TheAccountMFAEnabledproperty is set to1will ensure that the 'root' user account has MFA (Virtual or Hardware) Enabled. IfAccountMFAEnabledproperty is set to0the account is not compliant with this recommendation. 2. IfAccountMFAEnabledproperty is set to1, determine 'root' account has Hardware MFA enabled. Run the following command to list all virtual MFA devices:aws iam list-virtual-mfa-devicesIf the output contains one MFA with the following Serial Number, it means the MFA is virtual, not hardware and the account is not compliant with this recommendation:"SerialNumber": "arn:aws:iam::_<aws_account_number>_:mfa/root-account-mfa-device"- Assessment Status
Automated
- Rationale Statement
A hardware MFA has a smaller attack surface than a virtual MFA. For example, a hardware MFA does not suffer the attack surface introduced by the mobile smartphone on which a virtual MFA resides. Note: Using hardware MFA for many, many AWS accounts may create a logistical device management issue. If this is the case, consider implementing this Level 2 recommendation selectively to the highest security AWS accounts and the Level 1 recommendation applied to the remaining accounts.
- Remediation Procedure
Perform the following to establish a hardware MFA for the 'root' user account: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/iam/. Note: to manage MFA devices for the AWS 'root' user account, you must use your 'root' account credentials to sign in to AWS. You cannot manage MFA devices for the 'root' account using other credentials. 2. Choose
Dashboard, and underSecurity Status, expandActivate MFAon your root account. 3. ChooseActivate MFA4. In the wizard, chooseA hardware MFAdevice and then chooseNext Step. 5. In theSerial Numberbox, enter the serial number that is found on the back of the MFA device. 6. In theAuthentication Code 1box, enter the six-digit number displayed by the MFA device. You might need to press the button on the front of the device to display the number. 7. Wait 30 seconds while the device refreshes the code, and then enter the next six-digit number into theAuthentication Code 2box. You might need to press the button on the front of the device again to display the second number. 8. ChooseNext Step. The MFA device is now associated with the AWS account. The next time you use your AWS account credentials to sign in, you must type a code from the hardware MFA device. Remediation for this recommendation is not available through AWS CLI.- Additional Information
IAM User account 'root' for us-gov cloud regions does not have console access. This control is not applicable for us-gov cloud regions.
1.7Eliminate use of the 'root' user for administrative and daily tasks1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
With the creation of an AWS account, a 'root user' is created that cannot be disabled or deleted. That user has unrestricted access to and control over all resources in the AWS account. It is highly recommended that the use of this account be avoided for everyday tasks.
- Audit Procedure
From Console: 1. Login to the AWS Management Console at
https://console.aws.amazon.com/iam/2. In the left pane, clickCredential Report3. Click onDownload Report4. Open of Save the file locally 5. Locate the<root account>under the user column 6. Reviewpassword_last_used, access_key_1_last_used_date, access_key_2_last_used_dateto determine when the 'root user' was last used. From Command Line: Run the following CLI commands to provide a credential report for determining the last time the 'root user' was used:aws iam generate-credential-reportaws iam get-credential-report --query 'Content' --output text | base64 -d | cut -d, -f1,5,11,16 | grep -B1 '<root_account>'Reviewpassword_last_used,access_key_1_last_used_date,access_key_2_last_used_dateto determine when the root user was last used. Note: There are a few conditions under which the use of the 'root' user account is required. Please see the reference links for all of the tasks that require use of the 'root' user.- Assessment Status
Automated
- Rationale Statement
The 'root user' has unrestricted access to and control over all account resources. Use of it is inconsistent with the principles of least privilege and separation of duties, and can lead to unnecessary harm due to error or account compromise.
- Remediation Procedure
If you find that the 'root' user account is being used for daily activity to include administrative tasks that do not require the 'root' user: 1. Change the 'root' user password. 2. Deactivate or delete any access keys associate with the 'root' user. **Remember, anyone who has 'root' user credentials for your AWS account has unrestricted access to and control of all the resources in your account, including billing information.
- Additional Information
The 'root' user for us-gov cloud regions is not enabled by default. However, on request to AWS support, they can enable the 'root' user and grant access only through access-keys (CLI, API methods) for us-gov cloud region. If the 'root' user for us-gov cloud regions is enabled, this recommendation is applicable. Monitoring usage of the 'root' user can be accomplished by implementing recommendation 3.3 Ensure a log metric filter and alarm exist for usage of the 'root' user.
1.8Ensure IAM password policy requires minimum length of 14 or greater1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
Password policies are, in part, used to enforce password complexity requirements. IAM password policies can be used to ensure password are at least a given length. It is recommended that the password policy require a minimum password length 14.
- Audit Procedure
Perform the following to ensure the password policy is configured as prescribed: From Console: 1. Login to AWS Console (with appropriate permissions to View Identity Access Management Account Settings) 2. Go to IAM Service on the AWS Console 3. Click on Account Settings on the Left Pane 4. Ensure "Minimum password length" is set to 14 or greater. From Command Line:
aws iam get-account-password-policyEnsure the output of the above command includes "MinimumPasswordLength": 14 (or higher)- Assessment Status
Automated
- Rationale Statement
Setting a password complexity policy increases account resiliency against brute force login attempts.
- Remediation Procedure
Perform the following to set the password policy as prescribed: From Console: 1. Login to AWS Console (with appropriate permissions to View Identity Access Management Account Settings) 2. Go to IAM Service on the AWS Console 3. Click on Account Settings on the Left Pane 4. Set "Minimum password length" to
14or greater. 5. Click "Apply password policy" From Command Line:aws iam update-account-password-policy --minimum-password-length 14Note: All commands starting with "aws iam update-account-password-policy" can be combined into a single command.
1.9Ensure IAM password policy prevents password reuse1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
IAM password policies can prevent the reuse of a given password by the same user. It is recommended that the password policy prevent the reuse of passwords.
- Audit Procedure
Perform the following to ensure the password policy is configured as prescribed: From Console: 1. Login to AWS Console (with appropriate permissions to View Identity Access Management Account Settings) 2. Go to IAM Service on the AWS Console 3. Click on Account Settings on the Left Pane 4. Ensure "Prevent password reuse" is checked 5. Ensure "Number of passwords to remember" is set to 24 From Command Line:
aws iam get-account-password-policyEnsure the output of the above command includes "PasswordReusePrevention": 24- Assessment Status
Automated
- Rationale Statement
Preventing password reuse increases account resiliency against brute force login attempts.
- Remediation Procedure
Perform the following to set the password policy as prescribed: From Console: 1. Login to AWS Console (with appropriate permissions to View Identity Access Management Account Settings) 2. Go to IAM Service on the AWS Console 3. Click on Account Settings on the Left Pane 4. Check "Prevent password reuse" 5. Set "Number of passwords to remember" is set to
24From Command Line:aws iam update-account-password-policy --password-reuse-prevention 24Note: All commands starting with "aws iam update-account-password-policy" can be combined into a single command.
1.10Ensure multi-factor authentication (MFA) is enabled for all IAM users that have a console password1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
Multi-Factor Authentication (MFA) adds an extra layer of authentication assurance beyond traditional credentials. With MFA enabled, when a user signs in to the AWS Console, they will be prompted for their user name and password as well as for an authentication code from their physical or virtual MFA token. It is recommended that MFA be enabled for all accounts that have a console password.
- Audit Procedure
Perform the following to determine if a MFA device is enabled for all IAM users having a console password: From Console: 1. Open the IAM console at https://console.aws.amazon.com/iam/. 2. In the left pane, select
Users3. If theMFAorPassword agecolumns are not visible in the table, click the gear icon at the upper right corner of the table and ensure a checkmark is next to both, then clickClose. 4. Ensure that for each user where thePassword agecolumn shows a password age, theMFAcolumn showsVirtual,U2F Security Key, orHardware. From Command Line: 1. Run the following command (OSX/Linux/UNIX) to generate a list of all IAM users along with their password and MFA status:aws iam generate-credential-reportaws iam get-credential-report --query 'Content' --output text | base64 -d | cut -d, -f1,4,82. The output of this command will produce a table similar to the following:user,password_enabled,mfa_active elise,false,false brandon,true,true rakesh,false,false helene,false,false paras,true,true anitha,false,false3. For any column havingpassword_enabledset totrue, ensuremfa_activeis also set totrue.- Impact Statement
AWS will soon end support for SMS multi-factor authentication (MFA). New customers are not allowed to use this feature. We recommend that existing customers switch to one of the following alternative methods of MFA.
- Assessment Status
Automated
- Rationale Statement
Enabling MFA provides increased security for console access as it requires the authenticating principal to possess a device that displays a time-sensitive key and have knowledge of a credential.
- Remediation Procedure
Perform the following to enable MFA: From Console: 1. Sign in to the AWS Management Console and open the IAM console at 'https://console.aws.amazon.com/iam/' 2. In the left pane, select
Users. 3. In theUser Namelist, choose the name of the intended MFA user. 4. Choose theSecurity Credentialstab, and then chooseManage MFA Device. 5. In theManage MFA Device wizard, chooseVirtual MFAdevice, and then chooseContinue. IAM generates and displays configuration information for the virtual MFA device, including a QR code graphic. The graphic is a representation of the 'secret configuration key' that is available for manual entry on devices that do not support QR codes. 6. Open your virtual MFA application. (For a list of apps that you can use for hosting virtual MFA devices, see Virtual MFA Applications at https://aws.amazon.com/iam/details/mfa/#Virtual_MFA_Applications). If the virtual MFA application supports multiple accounts (multiple virtual MFA devices), choose the option to create a new account (a new virtual MFA device). 7. Determine whether the MFA app supports QR codes, and then do one of the following: - Use the app to scan the QR code. For example, you might choose the camera icon or choose an option similar to Scan code, and then use the device's camera to scan the code. - In the Manage MFA Device wizard, choose Show secret key for manual configuration, and then type the secret configuration key into your MFA application. When you are finished, the virtual MFA device starts generating one-time passwords. 8. In theManage MFA Device wizard, in theMFA Code 1 box, type theone-time passwordthat currently appears in the virtual MFA device. Wait up to 30 seconds for the device to generate a new one-time password. Then type the secondone-time passwordinto theMFA Code 2 box. 9. ClickAssign MFA.- Additional Information
Forced IAM User Self-Service Remediation Amazon has published a pattern that forces users to self-service setup MFA before they have access to their complete permissions set. Until they complete this step, they cannot access their full permissions. This pattern can be used on new AWS accounts. It can also be used on existing accounts - it is recommended users are given instructions and a grace period to accomplish MFA enrollment before active enforcement on existing AWS accounts.
1.11Do not setup access keys during initial user setup for all IAM users that have a console password1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
AWS console defaults to no check boxes selected when creating a new IAM user. When cerating the IAM User credentials you have to determine what type of access they require. Programmatic access: The IAM user might need to make API calls, use the AWS CLI, or use the Tools for Windows PowerShell. In that case, create an access key (access key ID and a secret access key) for that user. AWS Management Console access: If the user needs to access the AWS Management Console, create a password for the user.
- Audit Procedure
Perform the following to determine if access keys were created upon user creation and are being used and rotated as prescribed: From Console: 1. Login to the AWS Management Console 2. Click
Services3. ClickIAM4. Click on a User where columnPassword ageandAccess key ageis not set toNone5. Click onSecurity credentialsTab 6. Compare the user 'Creation timeto the Access KeyCreateddate. 6. For any that match, the key was created during initial user setup. - Keys that were created at the same time as the user profile and do not have a last used date should be deleted. Refer to the remediation below. **From Command Line:** 1. Run the following command (OSX/Linux/UNIX) to generate a list of all IAM users along with their access keys utilization: ``` aws iam generate-credential-report ``` ``` aws iam get-credential-report --query 'Content' --output text | base64 -d | cut -d, -f1,4,9,11,14,16 ``` 2. The output of this command will produce a table similar to the following: ``` user,password_enabled,access_key_1_active,access_key_1_last_used_date,access_key_2_active,access_key_2_last_used_date elise,false,true,2015-04-16T15:14:00+00:00,false,N/A brandon,true,true,N/A,false,N/A rakesh,false,false,N/A,false,N/A helene,false,true,2015-11-18T17:47:00+00:00,false,N/A paras,true,true,2016-08-28T12:04:00+00:00,true,2016-03-04T10:11:00+00:00 anitha,true,true,2016-06-08T11:43:00+00:00,true,N/A ``` 3. For any user havingpassword_enabledset totrueANDaccess_key_last_used_dateset toN/A` refer to the remediation below.- Assessment Status
Automated
- Rationale Statement
Requiring the additional steps be taken by the user for programmatic access after their profile has been created will give a stronger indication of intent that access keys are [a] necessary for their work and [b] once the access key is established on an account that the keys may be in use somewhere in the organization. Note: Even if it is known the user will need access keys, require them to create the keys themselves or put in a support ticket to have them created as a separate step from user creation.
- Remediation Procedure
Perform the following to delete access keys that do not pass the audit: From Console: 1. Login to the AWS Management Console: 2. Click
Services3. ClickIAM4. Click onUsers5. Click onSecurity Credentials6. As an Administrator - Click on the X(Delete)for keys that were created at the same time as the user profile but have not been used. 7. As an IAM User - Click on the X(Delete)for keys that were created at the same time as the user profile but have not been used. From Command Line:aws iam delete-access-key --access-key-id <access-key-id-listed> --user-name <users-name>- Additional Information
Credential report does not appear to contain "Key Creation Date"
1.12Ensure credentials unused for 45 days or greater are disabled2
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
AWS IAM users can access AWS resources using different types of credentials, such as passwords or access keys. It is recommended that all credentials that have been unused in 45 or greater days be deactivated or removed.
- Audit Procedure
Perform the following to determine if unused credentials exist: From Console: 1. Login to the AWS Management Console 2. Click
Services3. ClickIAM4. Click onUsers5. Click theSettings(gear) icon. 6. SelectConsole last sign-in,Access key last used, andAccess Key Id7. Click onClose8. Check and ensure thatConsole last sign-inis less than 45 days ago. Note -Nevermeans the user has never logged in. 9. Check and ensure thatAccess key ageis less than 45 days and thatAccess key last useddoes not sayNoneIf the user hasn't signed into the Console in the last 45 days or Access keys are over 45 days old refer to the remediation. From Command Line: Download Credential Report: 1. Run the following commands:aws iam generate-credential-report aws iam get-credential-report --query 'Content' --output text | base64 -d | cut -d, -f1,4,5,6,9,10,11,14,15,16 | grep -v '^<root_account>'Ensure unused credentials do not exist: 2. For each user havingpassword_enabledset toTRUE, ensurepassword_last_used_dateis less than45days ago. - Whenpassword_enabledis set toTRUEandpassword_last_usedis set toNo_Information, ensurepassword_last_changedis less than 45 days ago. 3. For each user having anaccess_key_1_activeoraccess_key_2_activetoTRUE, ensure the correspondingaccess_key_n_last_used_dateis less than45days ago. - When a user having anaccess_key_x_active(where x is 1 or 2) toTRUEand corresponding access_key_x_last_used_date is set toN/A', ensureaccess_key_x_last_rotated` is less than 45 days ago.- Assessment Status
Automated
- Rationale Statement
Disabling or removing unnecessary credentials will reduce the window of opportunity for credentials associated with a compromised or abandoned account to be used.
- Remediation Procedure
From Console: Perform the following to manage Unused Password (IAM user console access) 1. Login to the AWS Management Console: 2. Click
Services3. ClickIAM4. Click onUsers5. Click onSecurity Credentials6. Select user whoseConsole last sign-inis greater than 45 days 7. ClickSecurity credentials8. In sectionSign-in credentials,Console passwordclickManage9. Under Console Access selectDisable10.ClickApplyPerform the following to deactivate Access Keys: 1. Login to the AWS Management Console: 2. ClickServices3. ClickIAM4. Click onUsers5. Click onSecurity Credentials6. Select any access keys that are over 45 days old and that have been used and - Click onMake Inactive7. Select any access keys that are over 45 days old and that have not been used and - Click the X toDelete- Additional Information
<root_account> is excluded in the audit since the root account should not be used for day to day business and would likely be unused for more than 45 days.
1.13Ensure there is only one active access key available for any single IAM user1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
Access keys are long-term credentials for an IAM user or the AWS account 'root' user. You can use access keys to sign programmatic requests to the AWS CLI or AWS API (directly or using the AWS SDK)
- Audit Procedure
From Console: 1. Sign in to the AWS Management Console and navigate to IAM dashboard at
https://console.aws.amazon.com/iam/. 2. In the left navigation panel, chooseUsers. 3. Click on the IAM user name that you want to examine. 4. On the IAM user configuration page, selectSecurity Credentialstab. 5. UnderAccess Keyssection, in the Status column, check the current status for each access key associated with the IAM user. If the selected IAM user has more than one access key activated then the users access configuration does not adhere to security best practices and the risk of accidental exposures increases. - Repeat steps no. 3 – 5 for each IAM user in your AWS account. From Command Line: 1. Runlist-userscommand to list all IAM users within your account:aws iam list-users --query "Users[*].UserName"The command output should return an array that contains all your IAM user names. 2. Runlist-access-keyscommand using the IAM user name list to return the current status of each access key associated with the selected IAM user:aws iam list-access-keys --user-name <user-name>The command output should expose the metadata("Username", "AccessKeyId", "Status", "CreateDate")for each access key on that user account. 3. Check theStatusproperty value for each key returned to determine each keys current state. If theStatusproperty value for more than one IAM access key is set toActive, the user access configuration does not adhere to this recommendation, refer to the remediation below. - Repeat steps no. 2 and 3 for each IAM user in your AWS account.- Assessment Status
Automated
- Rationale Statement
Access keys are long-term credentials for an IAM user or the AWS account 'root' user. You can use access keys to sign programmatic requests to the AWS CLI or AWS API. One of the best ways to protect your account is to not allow users to have multiple access keys.
- Remediation Procedure
From Console: 1. Sign in to the AWS Management Console and navigate to IAM dashboard at
https://console.aws.amazon.com/iam/. 2. In the left navigation panel, chooseUsers. 3. Click on the IAM user name that you want to examine. 4. On the IAM user configuration page, selectSecurity Credentialstab. 5. InAccess Keyssection, choose one access key that is less than 90 days old. This should be the only active key used by this IAM user to access AWS resources programmatically. Test your application(s) to make sure that the chosen access key is working. 6. In the sameAccess Keyssection, identify your non-operational access keys (other than the chosen one) and deactivate it by clicking theMake Inactivelink. 7. If you receive theChange Key Statusconfirmation box, clickDeactivateto switch off the selected key. 8. Repeat steps no. 3 – 7 for each IAM user in your AWS account. From Command Line: 1. Using the IAM user and access key information provided in theAudit CLI, choose one access key that is less than 90 days old. This should be the only active key used by this IAM user to access AWS resources programmatically. Test your application(s) to make sure that the chosen access key is working. 2. Run theupdate-access-keycommand below using the IAM user name and the non-operational access key IDs to deactivate the unnecessary key(s). Refer to the Audit section to identify the unnecessary access key ID for the selected IAM user Note - the command does not return any output:aws iam update-access-key --access-key-id <access-key-id> --status Inactive --user-name <user-name>3. To confirm that the selected access key pair has been successfullydeactivatedrun thelist-access-keysaudit command again for that IAM User:aws iam list-access-keys --user-name <user-name>- The command output should expose the metadata for each access key associated with the IAM user. If the non-operational key pair(s)Statusis set toInactive, the key has been successfully deactivated and the IAM user access configuration adheres now to this recommendation. 4. Repeat steps no. 1 – 3 for each IAM user in your AWS account.
1.14Ensure access keys are rotated every 90 days or less1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
Access keys consist of an access key ID and secret access key, which are used to sign programmatic requests that you make to AWS. AWS users need their own access keys to make programmatic calls to AWS from the AWS Command Line Interface (AWS CLI), Tools for Windows PowerShell, the AWS SDKs, or direct HTTP calls using the APIs for individual AWS services. It is recommended that all access keys be regularly rotated.
- Audit Procedure
Perform the following to determine if access keys are rotated as prescribed: From Console: 1. Go to Management Console (https://console.aws.amazon.com/iam) 2. Click on
Users3. Clicksettingicon 4. SelectConsole last sign-in5. ClickClose6. Ensure thatAccess key ageis less than 90 days ago. note)Nonein theAccess key agemeans the user has not used the access key. From Command Line:aws iam generate-credential-report aws iam get-credential-report --query 'Content' --output text | base64 -dTheaccess_key_1_last_rotatedfield in this file notes The date and time, in ISO 8601 date-time format, when the user's access key was created or last changed. If the user does not have an active access key, the value in this field is N/A (not applicable).- Assessment Status
Automated
- Rationale Statement
Rotating access keys will reduce the window of opportunity for an access key that is associated with a compromised or terminated account to be used. Access keys should be rotated to ensure that data cannot be accessed with an old key which might have been lost, cracked, or stolen.
- Remediation Procedure
Perform the following to rotate access keys: From Console: 1. Go to Management Console (https://console.aws.amazon.com/iam) 2. Click on
Users3. Click onSecurity Credentials4. As an Administrator - Click onMake Inactivefor keys that have not been rotated in90Days 5. As an IAM User - Click onMake InactiveorDeletefor keys which have not been rotated or used in90Days 6. Click onCreate Access Key7. Update programmatic call with new Access Key credentials From Command Line: 1. While the first access key is still active, create a second access key, which is active by default. Run the following command:aws iam create-access-keyAt this point, the user has two active access keys. 2. Update all applications and tools to use the new access key. 3. Determine whether the first access key is still in use by using this command:aws iam get-access-key-last-used4. One approach is to wait several days and then check the old access key for any use before proceeding. Even if step Step 3 indicates no use of the old key, it is recommended that you do not immediately delete the first access key. Instead, change the state of the first access key to Inactive using this command:aws iam update-access-key5. Use only the new access key to confirm that your applications are working. Any applications and tools that still use the original access key will stop working at this point because they no longer have access to AWS resources. If you find such an application or tool, you can switch its state back to Active to reenable the first access key. Then return to step Step 2 and update this application to use the new key. 6. After you wait some period of time to ensure that all applications and tools have been updated, you can delete the first access key with this command:aws iam delete-access-key
1.15Ensure IAM Users Receive Permissions Only Through Groups1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
IAM users are granted access to services, functions, and data through IAM policies. There are three ways to define policies for a user: 1) Edit the user policy directly, aka an inline, or user, policy; 2) attach a policy directly to a user; 3) add the user to an IAM group that has an attached policy. Only the third implementation is recommended.
- Audit Procedure
Perform the following to determine if an inline policy is set or a policy is directly attached to users: 1. Run the following to get a list of IAM users:
aws iam list-users --query 'Users[*].UserName' --output text2. For each user returned, run the following command to determine if any policies are attached to them:aws iam list-attached-user-policies --user-name <iam_user> aws iam list-user-policies --user-name <iam_user>3. If any policies are returned, the user has an inline policy or direct policy attachment.- Assessment Status
Automated
- Rationale Statement
Assigning IAM policy only through groups unifies permissions management to a single, flexible layer consistent with organizational functional roles. By unifying permissions management, the likelihood of excessive permissions is reduced.
- Remediation Procedure
Perform the following to create an IAM group and assign a policy to it: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/iam/. 2. In the navigation pane, click
Groupsand then clickCreate New Group. 3. In theGroup Namebox, type the name of the group and then clickNext Step. 4. In the list of policies, select the check box for each policy that you want to apply to all members of the group. Then clickNext Step. 5. ClickCreate GroupPerform the following to add a user to a given group: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/iam/. 2. In the navigation pane, clickGroups3. Select the group to add a user to 4. ClickAdd Users To Group5. Select the users to be added to the group 6. ClickAdd UsersPerform the following to remove a direct association between a user and policy: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/iam/. 2. In the left navigation pane, click on Users 3. For each user: - Select the user - Click on thePermissionstab - ExpandPermissions policies- ClickXfor each policy; then click Detach or Remove (depending on policy type)
1.16Ensure IAM policies that allow full "*:*" administrative privileges are not attached2
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
IAM policies are the means by which privileges are granted to users, groups, or roles. It is recommended and considered a standard security advice to grant least privilege -that is, granting only the permissions required to perform a task. Determine what users need to do and then craft policies for them that let the users perform only those tasks, instead of allowing full administrative privileges.
- Audit Procedure
Perform the following to determine what policies are created: From Command Line: 1. Run the following to get a list of IAM policies:
aws iam list-policies --only-attached --output text2. For each policy returned, run the following command to determine if any policies is allowing full administrative privileges on the account:aws iam get-policy-version --policy-arn <policy_arn> --version-id <version>3. In output ensure policy should not have any Statement block with"Effect": "Allow"andActionset to"*"andResourceset to"*"- Assessment Status
Automated
- Rationale Statement
It's more secure to start with a minimum set of permissions and grant additional permissions as necessary, rather than starting with permissions that are too lenient and then trying to tighten them later. Providing full administrative privileges instead of restricting to the minimum set of permissions that the user is required to do exposes the resources to potentially unwanted actions. IAM policies that have a statement with "Effect": "Allow" with "Action": "*" over "Resource": "*" should be removed.
- Remediation Procedure
From Console: Perform the following to detach the policy that has full administrative privileges: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/iam/. 2. In the navigation pane, click Policies and then search for the policy name found in the audit step. 3. Select the policy that needs to be deleted. 4. In the policy action menu, select first Detach 5. Select all Users, Groups, Roles that have this policy attached 6. Click Detach Policy 7. In the policy action menu, select Detach 8. Select the newly detached policy and select Delete From Command Line: Perform the following to detach the policy that has full administrative privileges as found in the audit step: 1. Lists all IAM users, groups, and roles that the specified managed policy is attached to. aws iam list-entities-for-policy --policy-arn <policy_arn> 2. Detach the policy from all IAM Users: aws iam detach-user-policy --user-name <iam_user> --policy-arn <policy_arn> 3. Detach the policy from all IAM Groups: aws iam detach-group-policy --group-name <iam_group> --policy-arn <policy_arn> 4. Detach the policy from all IAM Roles: aws iam detach-role-policy --role-name <iam_role> --policy-arn <policy_arn>
1.17Ensure a support role has been created to manage incidents with AWS Support1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
AWS provides a support center that can be used for incident notification and response, as well as technical support and customer services. Create an IAM Role to allow authorized users to manage incidents with AWS Support.
- Audit Procedure
From Command Line: 1. List IAM policies, filter for the 'AWSSupportAccess' managed policy, and note the "Arn" element value:
aws iam list-policies --query "Policies[?PolicyName == 'AWSSupportAccess']"2. Check if the 'AWSSupportAccess' policy is attached to any role:aws iam list-entities-for-policy --policy-arn arn:aws:iam::aws:policy/AWSSupportAccess3. In Output, EnsurePolicyRolesdoes not return empty. 'Example: Example: PolicyRoles: [ ]' If it returns empty refer to the remediation below.- Impact Statement
All AWS Support plans include an unlimited number of account and billing supportcases, with no long-term contracts. Support billing calculations are performed on a per-account basis for all plans. Enterprise Support plan customers have the option toinclude multiple enabled accounts in an aggregated monthly billing calculation. Monthlycharges for the Business and Enterprise support plans are based on each month's AWSusage charges, subject to a monthly minimum, billed in advance.When assigning rights, keep in mind that other policies may grant access to Support aswell. This may include AdministratorAccess and other policies including customermanaged policies. Utilizing the AWS managed 'AWSSupportAccess' role is one simpleway of ensuring that this permission is properly granted.To better support the principle of separation of duties, it would be best to only attach thisrole where necessary.
- Assessment Status
Automated
- Rationale Statement
By implementing least privilege for access control, an IAM Role will require an appropriate IAM Policy to allow Support Center Access in order to manage Incidents with AWS Support.
- Remediation Procedure
From Command Line: 1. Create an IAM role for managing incidents with AWS: - Create a trust relationship policy document that allows <iam_user> to manage AWS incidents, and save it locally as /tmp/TrustPolicy.json:
{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Principal": { "AWS": "<iam_user>" }, "Action": "sts:AssumeRole" } ] }2. Create the IAM role using the above trust policy:aws iam create-role --role-name <aws_support_iam_role> --assume-role-policy-document file:///tmp/TrustPolicy.json3. Attach 'AWSSupportAccess' managed policy to the created IAM role:aws iam attach-role-policy --policy-arn arn:aws:iam::aws:policy/AWSSupportAccess --role-name <aws_support_iam_role>- Additional Information
AWSSupportAccess policy is a global AWS resource. It has same ARN as
arn:aws:iam::aws:policy/AWSSupportAccessfor every account.
1.18Ensure IAM instance roles are used for AWS resource access from instances1
Attributes
- Profile
Level 2
- Section
1 Identity and Access Management
- Description
AWS access from within AWS instances can be done by either encoding AWS keys into AWS API calls or by assigning the instance to a role which has an appropriate permissions policy for the required access. "AWS Access" means accessing the APIs of AWS in order to access AWS resources or manage AWS account resources.
- Audit Procedure
Where an instance is associated with a Role: For instances that are known to perform AWS actions, ensure that they belong to an instance role that has the necessary permissions: 1. Login to AWS Console (with appropriate permissions to View Identity Access Management Account Settings) 2. Open the EC2 Dashboard and choose "Instances" 3. Click the EC2 instance that performs AWS actions, in the lower pane details find "IAM Role" 4. If the Role is blank, the instance is not assigned to one. 5. If the Role is filled in, it does not mean the instance might not *also* have credentials encoded on it for some activities. Where an Instance Contains Embedded Credentials: - On the instance that is known to perform AWS actions, audit all scripts and environment variables to ensure that none of them contain AWS credentials. Where an Instance Application Contains Embedded Credentials: - Applications that run on an instance may also have credentials embedded. This is a bad practice, but even worse if the source code is stored in a public code repository such as github. When an application contains credentials can be determined by eliminating all other sources of credentials and if the application can still access AWS resources - it likely contains embedded credentials. Another method is to examine all source code and configuration files of the application.
- Assessment Status
Manual
- Rationale Statement
AWS IAM roles reduce the risks associated with sharing and rotating credentials that can be used outside of AWS itself. If credentials are compromised, they can be used from outside of the AWS account they give access to. In contrast, in order to leverage role permissions an attacker would need to gain and maintain access to a specific instance to use the privileges associated with it. Additionally, if credentials are encoded into compiled applications or other hard to change mechanisms, then they are even more unlikely to be properly rotated due to service disruption risks. As time goes on, credentials that cannot be rotated are more likely to be known by an increasing number of individuals who no longer work for the organization owning the credentials.
- Remediation Procedure
IAM roles can only be associated at the launch of an instance. To remediate an instance to add it to a role you must create a new instance. If the instance has no external dependencies on its current private ip or public addresses are elastic IPs: 1. In AWS IAM create a new role. Assign a permissions policy if needed permissions are already known. 2. In the AWS console launch a new instance with identical settings to the existing instance, and ensure that the newly created role is selected. 3. Shutdown both the existing instance and the new instance. 4. Detach disks from both instances. 5. Attach the existing instance disks to the new instance. 6. Boot the new instance and you should have the same machine, but with the associated role. Note: if your environment has dependencies on a dynamically assigned PRIVATE IP address you can create an AMI from the existing instance, destroy the old one and then when launching from the AMI, manually assign the previous private IP address. **Note: **if your environment has dependencies on a dynamically assigned PUBLIC IP address there is not a way ensure the address is retained and assign an instance role. Dependencies on dynamically assigned public IP addresses are a bad practice and, if possible, you may wish to rebuild the instance with a new elastic IP address and make the investment to remediate affected systems while assigning the system to a role.
1.19Ensure that all the expired SSL/TLS certificates stored in AWS IAM are removed1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
To enable HTTPS connections to your website or application in AWS, you need an SSL/TLS server certificate. You can use ACM or IAM to store and deploy server certificates. Use IAM as a certificate manager only when you must support HTTPS connections in a region that is not supported by ACM. IAM securely encrypts your private keys and stores the encrypted version in IAM SSL certificate storage. IAM supports deploying server certificates in all regions, but you must obtain your certificate from an external provider for use with AWS. You cannot upload an ACM certificate to IAM. Additionally, you cannot manage your certificates from the IAM Console.
- Audit Procedure
From Console: Getting the certificates expiration information via AWS Management Console is not currently supported. To request information about the SSL/TLS certificates stored in IAM via the AWS API use the Command Line Interface (CLI). From Command Line: Run list-server-certificates command to list all the IAM-stored server certificates:
aws iam list-server-certificatesThe command output should return an array that contains all the SSL/TLS certificates currently stored in IAM and their metadata (name, ID, expiration date, etc):{ "ServerCertificateMetadataList": [ { "ServerCertificateId": "EHDGFRW7EJFYTE88D", "ServerCertificateName": "MyServerCertificate", "Expiration": "2018-07-10T23:59:59Z", "Path": "/", "Arn": "arn:aws:iam::012345678910:server-certificate/MySSLCertificate", "UploadDate": "2018-06-10T11:56:08Z" } ] }Verify theServerCertificateNameandExpirationparameter value (expiration date) for each SSL/TLS certificate returned by the list-server-certificates command and determine if there are any expired server certificates currently stored in AWS IAM. If so, use the AWS API to remove them. If this command returns:{ { "ServerCertificateMetadataList": [] }This means that there are no expired certificates, It DOES NOT mean that no certificates exist.- Impact Statement
Deleting the certificate could have implications for your application if you are using an expired server certificate with Elastic Load Balancing, CloudFront, etc. One has to make configurations at respective services to ensure there is no interruption in application functionality.
- Assessment Status
Automated
- Rationale Statement
Removing expired SSL/TLS certificates eliminates the risk that an invalid certificate will be deployed accidentally to a resource such as AWS Elastic Load Balancer (ELB), which can damage the credibility of the application/website behind the ELB. As a best practice, it is recommended to delete expired certificates.
- Remediation Procedure
From Console: Removing expired certificates via AWS Management Console is not currently supported. To delete SSL/TLS certificates stored in IAM via the AWS API use the Command Line Interface (CLI). From Command Line: To delete Expired Certificate run following command by replacing <CERTIFICATE_NAME> with the name of the certificate to delete:
aws iam delete-server-certificate --server-certificate-name <CERTIFICATE_NAME>When the preceding command is successful, it does not return any output.
1.20Ensure that IAM Access analyzer is enabled for all regions1
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
Enable IAM Access analyzer for IAM policies about all resources in each region. IAM Access Analyzer is a technology introduced at AWS reinvent 2019. After the Analyzer is enabled in IAM, scan results are displayed on the console showing the accessible resources. Scans show resources that other accounts and federated users can access, such as KMS keys and IAM roles. So the results allow you to determine if an unintended user is allowed, making it easier for administrators to monitor least privileges access. Access Analyzer analyzes only policies that are applied to resources in the same AWS Region.
- Audit Procedure
From Console: 1. Open the IAM console at
https://console.aws.amazon.com/iam/2. ChooseAccess analyzer3. Click 'Analyzers' 4. Ensure that at least one analyzer is present 5. Ensure that theSTATUSis set toActive6. Repeat these step for each active region From Command Line: 1. Run the following command:aws accessanalyzer list-analyzers | grep status2. Ensure that at least one Analyzer thestatusis set toACTIVE3. Repeat the steps above for each active region. If an Access analyzer is not listed for each region or the status is not set to active refer to the remediation procedure below.- Assessment Status
Automated
- Rationale Statement
AWS IAM Access Analyzer helps you identify the resources in your organization and accounts, such as Amazon S3 buckets or IAM roles, that are shared with an external entity. This lets you identify unintended access to your resources and data. Access Analyzer identifies resources that are shared with external principals by using logic-based reasoning to analyze the resource-based policies in your AWS environment. IAM Access Analyzer continuously monitors all policies for S3 bucket, IAM roles, KMS(Key Management Service) keys, AWS Lambda functions, and Amazon SQS(Simple Queue Service) queues.
- Remediation Procedure
From Console: Perform the following to enable IAM Access analyzer for IAM policies: 1. Open the IAM console at
https://console.aws.amazon.com/iam/.2. ChooseAccess analyzer. 3. ChooseCreate analyzer. 4. On theCreate analyzerpage, confirm that theRegiondisplayed is the Region where you want to enable Access Analyzer. 5. Enter a name for the analyzer.Optional as it will generate a name for you automatically. 6. Add any tags that you want to apply to the analyzer.Optional. 7. ChooseCreate Analyzer. 8. Repeat these step for each active region From Command Line: Run the following command:aws accessanalyzer create-analyzer --analyzer-name <NAME> --type <ACCOUNT|ORGANIZATION>Repeat this command above for each active region. Note: The IAM Access Analyzer is successfully configured only when the account you use has the necessary permissions.
1.21Ensure IAM users are managed centrally via identity federation or AWS Organizations for multi-account environments1
Attributes
- Profile
Level 2
- Section
1 Identity and Access Management
- Description
In multi-account environments, IAM user centralization facilitates greater user control. User access beyond the initial account is then provided via role assumption. Centralization of users can be accomplished through federation with an external identity provider or through the use of AWS Organizations.
- Audit Procedure
For multi-account AWS environments with an external identity provider: 1. Determine the master account for identity federation or IAM user management 2. Login to that account through the AWS Management Console 3. Click Services 4. Click IAM 5. Click Identity providers 6. Verify the configuration Then, determine all accounts that should not have local users present. For each account: 1. Determine all accounts that should not have local users present 2. Log into the AWS Management Console 3. Switch role into each identified account 4. Click Services 5. Click IAM 6. Click Users 7. Confirm that no IAM users representing individuals are present For multi-account AWS environments implementing AWS Organizations without an external identity provider: 1. Determine all accounts that should not have local users present 2. Log into the AWS Management Console 3. Switch role into each identified account 4. Click Services 5. Click IAM 6. Click Users 7. Confirm that no IAM users representing individuals are present
- Assessment Status
Manual
- Rationale Statement
Centralizing IAM user management to a single identity store reduces complexity and thus the likelihood of access management errors.
- Remediation Procedure
The remediation procedure will vary based on the individual organization's implementation of identity federation and/or AWS Organizations with the acceptance criteria that no non-service IAM users, and non-root accounts, are present outside the account providing centralized IAM user management.
1.22Ensure access to AWSCloudShellFullAccess is restricted0
Attributes
- Profile
Level 1
- Section
1 Identity and Access Management
- Description
AWS CloudShell is a convenient way of running CLI commands against AWS services; a managed IAM policy ('AWSCloudShellFullAccess') provides full access to CloudShell, which allows file upload and download capability between a user's local system and the CloudShell environment. Within the CloudShell environment a user has sudo permissions, and can access the internet. So it is feasible to install file transfer software (for example) and move data from CloudShell to external internet servers.
- Audit Procedure
From Console 1. Open the IAM console at https://console.aws.amazon.com/iam/ 2. In the left pane, select Policies 3. Search for and select AWSCloudShellFullAccess 4. On the Entities attached tab, ensure that there are no entities using this policy From Command Line 1. List IAM policies, filter for the 'AWSCloudShellFullAccess' managed policy, and note the ""Arn"" element value:
aws iam list-policies --query ""Policies[?PolicyName == 'AWSCloudShellFullAccess']""2. Check if the 'AWSCloudShellFullAccess' policy is attached to any role:aws iam list-entities-for-policy --policy-arn arn:aws:iam::aws:policy/AWSCloudShellFullAccess3. In Output, Ensure PolicyRoles returns empty. 'Example: Example: PolicyRoles: [ ]' If it does not return empty refer to the remediation below. Note: Keep in mind that other policies may grant access.- Assessment Status
Manual
- Rationale Statement
Access to this policy should be restricted as it presents a potential channel for data exfiltration by malicious cloud admins that are given full permissions to the service. AWS documentation describes how to create a more restrictive IAM policy which denies file transfer permissions.
- Remediation Procedure
From Console 1. Open the IAM console at https://console.aws.amazon.com/iam/ 2. In the left pane, select Policies 3. Search for and select AWSCloudShellFullAccess 4. On the Entities attached tab, for each item, check the box and select Detach
2 Storage910
2.1.1Ensure S3 Bucket Policy is set to deny HTTP requests1
Attributes
- Profile
Level 2
- Section
2 Storage
- Sub Section
2.1 Simple Storage Service (S3)
- Description
At the Amazon S3 bucket level, you can configure permissions through a bucket policy making the objects accessible only through HTTPS.
- Audit Procedure
To allow access to HTTPS you can use a condition that checks for the key
"aws:SecureTransport: true". This means that the request is sent through HTTPS but that HTTP can still be used. So to make sure you do not allow HTTP access confirm that there is a bucket policy that explicitly denies access for HTTP requests and that it contains the key "aws:SecureTransport": "false". From Console: 1. Login to AWS Management Console and open the Amazon S3 console using https://console.aws.amazon.com/s3/ 2. Select the Check box next to the Bucket. 3. Click on 'Permissions', then Click onBucket Policy. 4. Ensure that a policy is listed that matches:'{ "Sid": <optional>, "Effect": "Deny", "Principal": "*", "Action": "s3:*", "Resource": "arn:aws:s3:::<bucket_name>/*", "Condition": { "Bool": { "aws:SecureTransport": "false" }'<optional>and<bucket_name>will be specific to your account 5. Repeat for all the buckets in your AWS account. From Command Line: 1. List all of the S3 Bucketsaws s3 ls2. Using the list of buckets run this command on each of them:aws s3api get-bucket-policy --bucket <bucket_name> | grep aws:SecureTransport3. Confirm thataws:SecureTransportis set to falseaws:SecureTransport:false4. Confirm that the policy line has Effect set to Deny 'Effect:Deny'- Assessment Status
Automated
- Rationale Statement
By default, Amazon S3 allows both HTTP and HTTPS requests. To achieve only allowing access to Amazon S3 objects through HTTPS you also have to explicitly deny access to HTTP requests. Bucket policies that allow HTTPS requests without explicitly denying HTTP requests will not comply with this recommendation.
- Remediation Procedure
From Console: 1. Login to AWS Management Console and open the Amazon S3 console using https://console.aws.amazon.com/s3/ 2. Select the Check box next to the Bucket. 3. Click on 'Permissions'. 4. Click 'Bucket Policy' 5. Add this to the existing policy filling in the required information
{ "Sid": <optional>", "Effect": "Deny", "Principal": "*", "Action": "s3:*", "Resource": "arn:aws:s3:::<bucket_name>/*", "Condition": { "Bool": { "aws:SecureTransport": "false" } } }6. Save 7. Repeat for all the buckets in your AWS account that contain sensitive data. From Console using AWS Policy Generator: 1. Repeat steps 1-4 above. 2. Click onPolicy Generatorat the bottom of the Bucket Policy Editor 3. Select Policy TypeS3 Bucket Policy4. Add Statements -Effect= Deny -Principal= * -AWS Service= Amazon S3 -Actions= * -Amazon Resource Name= <ARN of the S3 Bucket> 5. Generate Policy 6. Copy the text and add it to the Bucket Policy. From Command Line: 1. Export the bucket policy to a json file.aws s3api get-bucket-policy --bucket <bucket_name> --query Policy --output text > policy.json2. Modify the policy.json file by adding in this statement:{ "Sid": <optional>", "Effect": "Deny", "Principal": "*", "Action": "s3:*", "Resource": "arn:aws:s3:::<bucket_name>/*", "Condition": { "Bool": { "aws:SecureTransport": "false" } } }3. Apply this modified policy back to the S3 bucket:aws s3api put-bucket-policy --bucket <bucket_name> --policy file://policy.json
2.1.2Ensure MFA Delete is enabled on S3 buckets1
Attributes
- Profile
Level 1
- Section
2 Storage
- Sub Section
2.1 Simple Storage Service (S3)
- Description
Once MFA Delete is enabled on your sensitive and classified S3 bucket it requires the user to have two forms of authentication.
- Audit Procedure
Perform the steps below to confirm MFA delete is configured on an S3 Bucket From Console: 1. Login to the S3 console at
https://console.aws.amazon.com/s3/2. Click theCheckbox next to the Bucket name you want to confirm 3. In the window underProperties4. Confirm that Versioning isEnabled5. Confirm that MFA Delete isEnabledFrom Command Line: 1. Run theget-bucket-versioningaws s3api get-bucket-versioning --bucket my-bucketOutput example:<VersioningConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/"> <Status>Enabled</Status> <MfaDelete>Enabled</MfaDelete> </VersioningConfiguration>If the Console or the CLI output does not show Versioning and MFA Deleteenabledrefer to the remediation below.- Assessment Status
Automated
- Rationale Statement
Adding MFA delete to an S3 bucket, requires additional authentication when you change the version state of your bucket or you delete and object version adding another layer of security in the event your security credentials are compromised or unauthorized access is granted.
- Remediation Procedure
Perform the steps below to enable MFA delete on an S3 bucket. Note: -You cannot enable MFA Delete using the AWS Management Console. You must use the AWS CLI or API. -You must use your 'root' account to enable MFA Delete on S3 buckets. From Command line: 1. Run the s3api put-bucket-versioning command
aws s3api put-bucket-versioning --profile my-root-profile --bucket Bucket_Name --versioning-configuration Status=Enabled,MFADelete=Enabled --mfa “arn:aws:iam::aws_account_id:mfa/root-account-mfa-device passcode”
2.1.3Ensure all data in Amazon S3 has been discovered, classified and secured when required.1
Attributes
- Profile
Level 2
- Section
2 Storage
- Sub Section
2.1 Simple Storage Service (S3)
- Description
Amazon S3 buckets can contain sensitive data, that for security purposes should be discovered, monitored, classified and protected. Macie along with other 3rd party tools can automatically provide an inventory of Amazon S3 buckets.
- Audit Procedure
Perform the following steps to determine if Macie is running: From Console: 1. Login to the Macie console at https://console.aws.amazon.com/macie/ 2. In the left hand pane click on By job under findings. 3. Confirm that you have a Job setup for your S3 Buckets When you log into the Macie console if you aren't taken to the summary page and you don't have a job setup and running then refer to the remediation procedure below. If you are using a 3rd Party tool to manage and protect your s3 data you meet this recommendation.
- Impact Statement
There is a cost associated with using Amazon Macie. There is also typically a cost associated with 3rd Party tools that perform similar processes and protection.
- Assessment Status
Manual
- Rationale Statement
Using a Cloud service or 3rd Party software to continuously monitor and automate the process of data discovery and classification for S3 buckets using machine learning and pattern matching is a strong defense in protecting that information. Amazon Macie is a fully managed data security and data privacy service that uses machine learning and pattern matching to discover and protect your sensitive data in AWS.
- Remediation Procedure
Perform the steps below to enable and configure Amazon Macie From Console: 1. Log on to the Macie console at
https://console.aws.amazon.com/macie/2. ClickGet started. 3. ClickEnable Macie. Setup a repository for sensitive data discovery results 1. In the Left pane, under Settings, clickDiscovery results. 2. Make sureCreate bucketis selected. 3. Create a bucket, enter a name for the bucket. The name must be unique across all S3 buckets. In addition, the name must start with a lowercase letter or a number. 4. Click onAdvanced. 5. Block all public access, make sureYesis selected. 6. KMS encryption, specify the AWS KMS key that you want to use to encrypt the results. The key must be a symmetric, customer master key (CMK) that's in the same Region as the S3 bucket. 7. Click onSaveCreate a job to discover sensitive data 1. In the left pane, clickS3 buckets. Macie displays a list of all the S3 buckets for your account. 2. Select thecheck boxfor each bucket that you want Macie to analyze as part of the job 3. ClickCreate job. 3. ClickQuick create. 4. For the Name and description step, enter a name and, optionally, a description of the job. 5. Then clickNext. 6. For the Review and create step, clickSubmit. Review your findings 1. In the left pane, clickFindings. 2. To view the details of a specific finding, choose any field other than the check box for the finding. If you are using a 3rd Party tool to manage and protect your s3 data, follow the Vendor documentation for implementing and configuring that tool.
2.1.4Ensure that S3 Buckets are configured with 'Block public access (bucket settings)'2
Attributes
- Profile
Level 1
- Section
2 Storage
- Sub Section
2.1 Simple Storage Service (S3)
- Description
Amazon S3 provides
Block public access (bucket settings)andBlock public access (account settings)to help you manage public access to Amazon S3 resources. By default, S3 buckets and objects are created with public access disabled. However, an IAM principal with sufficient S3 permissions can enable public access at the bucket and/or object level. While enabled,Block public access (bucket settings)prevents an individual bucket, and its contained objects, from becoming publicly accessible. Similarly,Block public access (account settings)prevents all buckets, and contained objects, from becoming publicly accessible across the entire account.- Audit Procedure
If utilizing Block Public Access (bucket settings) From Console: 1. Login to AWS Management Console and open the Amazon S3 console using https://console.aws.amazon.com/s3/ 2. Select the Check box next to the Bucket. 3. Click on 'Edit public access settings'. 4. Ensure that block public access settings are set appropriately for this bucket 5. Repeat for all the buckets in your AWS account. From Command Line: 1. List all of the S3 Buckets
aws s3 ls2. Find the public access setting on that bucketaws s3api get-public-access-block --bucket <name-of-the-bucket>Output if Block Public access is enabled:{ "PublicAccessBlockConfiguration": { "BlockPublicAcls": true, "IgnorePublicAcls": true, "BlockPublicPolicy": true, "RestrictPublicBuckets": true } }If the output readsfalsefor the separate configuration settings then proceed to the remediation. If utilizing Block Public Access (account settings) From Console: 1. Login to AWS Management Console and open the Amazon S3 console using https://console.aws.amazon.com/s3/ 2. ChooseBlock public access (account settings)3. Ensure that block public access settings are set appropriately for your AWS account. From Command Line: To check Public access settings for this account status, run the following command,aws s3control get-public-access-block --account-id <ACCT_ID> --region <REGION_NAME>Output if Block Public access is enabled:{ "PublicAccessBlockConfiguration": { "IgnorePublicAcls": true, "BlockPublicPolicy": true, "BlockPublicAcls": true, "RestrictPublicBuckets": true } }If the output readsfalsefor the separate configuration settings then proceed to the remediation.- Impact Statement
When you apply Block Public Access settings to an account, the settings apply to all AWS Regions globally. The settings might not take effect in all Regions immediately or simultaneously, but they eventually propagate to all Regions.
- Assessment Status
Automated
- Rationale Statement
Amazon S3
Block public access (bucket settings)prevents the accidental or malicious public exposure of data contained within the respective bucket(s). Amazon S3Block public access (account settings)prevents the accidental or malicious public exposure of data contained within all buckets of the respective AWS account. Whether blocking public access to all or some buckets is an organizational decision that should be based on data sensitivity, least privilege, and use case.- Remediation Procedure
If utilizing Block Public Access (bucket settings) From Console: 1. Login to AWS Management Console and open the Amazon S3 console using https://console.aws.amazon.com/s3/ 2. Select the Check box next to the Bucket. 3. Click on 'Edit public access settings'. 4. Click 'Block all public access' 5. Repeat for all the buckets in your AWS account that contain sensitive data. From Command Line: 1. List all of the S3 Buckets
aws s3 ls2. Set the Block Public Access to true on that bucketaws s3api put-public-access-block --bucket <name-of-bucket> --public-access-block-configuration "BlockPublicAcls=true,IgnorePublicAcls=true,BlockPublicPolicy=true,RestrictPublicBuckets=true"If utilizing Block Public Access (account settings) From Console: If the output readstruefor the separate configuration settings then it is set on the account. 1. Login to AWS Management Console and open the Amazon S3 console using https://console.aws.amazon.com/s3/ 2. ChooseBlock Public Access (account settings)3. ChooseEditto change the block public access settings for all the buckets in your AWS account 4. Choose the settings you want to change, and then chooseSave. For details about each setting, pause on theiicons. 5. When you're asked for confirmation, enterconfirm. Then ClickConfirmto save your changes. From Command Line: To set Block Public access settings for this account, run the following command:aws s3control put-public-access-block --public-access-block-configuration BlockPublicAcls=true, IgnorePublicAcls=true, BlockPublicPolicy=true, RestrictPublicBuckets=true --account-id <value>
2.2.1Ensure EBS Volume Encryption is Enabled in all Regions1
Attributes
- Profile
Level 1
- Section
2 Storage
- Sub Section
2.2 Elastic Compute Cloud (EC2)
- Description
Elastic Compute Cloud (EC2) supports encryption at rest when using the Elastic Block Store (EBS) service. While disabled by default, forcing encryption at EBS volume creation is supported.
- Audit Procedure
From Console: 1. Login to AWS Management Console and open the Amazon EC2 console using https://console.aws.amazon.com/ec2/ 2. Under
Account attributes, clickEBS encryption. 3. VerifyAlways encrypt new EBS volumesdisplaysEnabled. 4. Review every region in-use. Note: EBS volume encryption is configured per region. From Command Line: 1. Runaws --region <region> ec2 get-ebs-encryption-by-default2. Verify that"EbsEncryptionByDefault": trueis displayed. 3. Review every region in-use. Note: EBS volume encryption is configured per region.- Impact Statement
Losing access or removing the KMS key in use by the EBS volumes will result in no longer being able to access the volumes.
- Assessment Status
Automated
- Rationale Statement
Encrypting data at rest reduces the likelihood that it is unintentionally exposed and can nullify the impact of disclosure if the encryption remains unbroken.
- Remediation Procedure
From Console: 1. Login to AWS Management Console and open the Amazon EC2 console using https://console.aws.amazon.com/ec2/ 2. Under
Account attributes, clickEBS encryption. 3. ClickManage. 4. Click theEnablecheckbox. 5. ClickUpdate EBS encryption6. Repeat for every region requiring the change. Note: EBS volume encryption is configured per region. From Command Line: 1. Runaws --region <region> ec2 enable-ebs-encryption-by-default2. Verify that"EbsEncryptionByDefault": trueis displayed. 3. Repeat every region requiring the change. Note: EBS volume encryption is configured per region.- Additional Information
Default EBS volume encryption only applies to newly created EBS volumes. Existing EBS volumes are not converted automatically.
2.3.1Ensure that encryption is enabled for RDS Instances1
Attributes
- Profile
Level 1
- Section
2 Storage
- Sub Section
2.3 Relational Database Service (RDS)
- Description
Amazon RDS encrypted DB instances use the industry standard AES-256 encryption algorithm to encrypt your data on the server that hosts your Amazon RDS DB instances. After your data is encrypted, Amazon RDS handles authentication of access and decryption of your data transparently with a minimal impact on performance.
- Audit Procedure
From Console: 1. Login to the AWS Management Console and open the RDS dashboard at https://console.aws.amazon.com/rds/ 2. In the navigation pane, under RDS dashboard, click
Databases. 3. Select the RDS Instance that you want to examine 4. ClickInstance Nameto see details, then click onConfigurationtab. 5. Under Configuration Details section, In Storage pane search for theEncryption EnabledStatus. 6. If the current status is set toDisabled, Encryption is not enabled for the selected RDS Instance database instance. 7. Repeat steps 3 to 7 to verify encryption status of other RDS Instance in same region. 8. Change region from the top of the navigation bar and repeat audit for other regions. From Command Line: 1. Rundescribe-db-instancescommand to list all RDS Instance database names, available in the selected AWS region, Output will return each Instance database identifier-name.aws rds describe-db-instances --region <region-name> --query 'DBInstances[*].DBInstanceIdentifier'2. Run againdescribe-db-instancescommand using the RDS Instance identifier returned earlier, to determine if the selected database instance is encrypted, The command output should return the encryption statusTrueOrFalse.aws rds describe-db-instances --region <region-name> --db-instance-identifier <DB-Name> --query 'DBInstances[*].StorageEncrypted'3. If the StorageEncrypted parameter value isFalse, Encryption is not enabled for the selected RDS database instance. 4. Repeat steps 1 to 3 for auditing each RDS Instance and change Region to verify for other regions- Assessment Status
Automated
- Rationale Statement
Databases are likely to hold sensitive and critical data, it is highly recommended to implement encryption in order to protect your data from unauthorized access or disclosure. With RDS encryption enabled, the data stored on the instance's underlying storage, the automated backups, read replicas, and snapshots, are all encrypted.
- Remediation Procedure
From Console: 1. Login to the AWS Management Console and open the RDS dashboard at https://console.aws.amazon.com/rds/. 2. In the left navigation panel, click on
Databases3. Select the Database instance that needs to be encrypted. 4. Click onActionsbutton placed at the top right and selectTake Snapshot. 5. On the Take Snapshot page, enter a database name of which you want to take a snapshot in theSnapshot Namefield and click onTake Snapshot. 6. Select the newly created snapshot and click on theActionbutton placed at the top right and selectCopy snapshotfrom the Action menu. 7. On the Make Copy of DB Snapshot page, perform the following: - In the New DB Snapshot Identifier field, Enter a name for thenew snapshot. - CheckCopy Tags, New snapshot must have the same tags as the source snapshot. - SelectYesfrom theEnable Encryptiondropdown list to enable encryption, You can choose to use the AWS default encryption key or custom key from Master Key dropdown list. 8. ClickCopy Snapshotto create an encrypted copy of the selected instance snapshot. 9. Select the new Snapshot Encrypted Copy and click on theActionbutton placed at the top right and selectRestore Snapshotbutton from the Action menu, This will restore the encrypted snapshot to a new database instance. 10. On the Restore DB Instance page, enter a unique name for the new database instance in the DB Instance Identifier field. 11. Review the instance configuration details and clickRestore DB Instance. 12. As the new instance provisioning process is completed can update application configuration to refer to the endpoint of the new Encrypted database instance Once the database endpoint is changed at the application level, can remove the unencrypted instance. From Command Line: 1. Rundescribe-db-instancescommand to list all RDS database names available in the selected AWS region, The command output should return the database instance identifier.aws rds describe-db-instances --region <region-name> --query 'DBInstances[*].DBInstanceIdentifier'2. Runcreate-db-snapshotcommand to create a snapshot for the selected database instance, The command output will return thenew snapshotwith name DB Snapshot Name.aws rds create-db-snapshot --region <region-name> --db-snapshot-identifier <DB-Snapshot-Name> --db-instance-identifier <DB-Name>3. Now runlist-aliasescommand to list the KMS keys aliases available in a specified region, The command output should return eachkey alias currently available. For our RDS encryption activation process, locate the ID of the AWS default KMS key.aws kms list-aliases --region <region-name>4. Runcopy-db-snapshotcommand using the default KMS key ID for RDS instances returned earlier to create an encrypted copy of the database instance snapshot, The command output will return theencrypted instance snapshot configuration.aws rds copy-db-snapshot --region <region-name> --source-db-snapshot-identifier <DB-Snapshot-Name> --target-db-snapshot-identifier <DB-Snapshot-Name-Encrypted> --copy-tags --kms-key-id <KMS-ID-For-RDS>5. Runrestore-db-instance-from-db-snapshotcommand to restore the encrypted snapshot created at the previous step to a new database instance, If successful, the command output should return the new encrypted database instance configuration.aws rds restore-db-instance-from-db-snapshot --region <region-name> --db-instance-identifier <DB-Name-Encrypted> --db-snapshot-identifier <DB-Snapshot-Name-Encrypted>6. Rundescribe-db-instancescommand to list all RDS database names, available in the selected AWS region, Output will return database instance identifier name Select encrypted database name that we just created DB-Name-Encrypted.aws rds describe-db-instances --region <region-name> --query 'DBInstances[*].DBInstanceIdentifier'7. Run againdescribe-db-instancescommand using the RDS instance identifier returned earlier, to determine if the selected database instance is encrypted, The command output should return the encryption statusTrue.aws rds describe-db-instances --region <region-name> --db-instance-identifier <DB-Name-Encrypted> --query 'DBInstances[*].StorageEncrypted'
2.3.2Ensure Auto Minor Version Upgrade feature is Enabled for RDS Instances1
Attributes
- Profile
Level 1
- Section
2 Storage
- Sub Section
2.3 Relational Database Service (RDS)
- Description
Ensure that RDS database instances have the Auto Minor Version Upgrade flag enabled in order to receive automatically minor engine upgrades during the specified maintenance window. So, RDS instances can get the new features, bug fixes, and security patches for their database engines.
- Audit Procedure
From Console: 1. Log in to the AWS management console and navigate to the RDS dashboard at https://console.aws.amazon.com/rds/. 2. In the left navigation panel, click on
Databases. 3. Select the RDS instance that wants to examine. 4. Click on theMaintenance and backupspanel. 5. Under theMaintenancesection, search for the Auto Minor Version Upgrade status. - If the current status is set toDisabled, means the feature is not set and the minor engine upgrades released will not be applied to the selected RDS instance From Command Line: 1. Rundescribe-db-instancescommand to list all RDS database names, available in the selected AWS region:aws rds describe-db-instances --region <regionName> --query 'DBInstances[*].DBInstanceIdentifier'2. The command output should return each database instance identifier. 3. Run againdescribe-db-instancescommand using the RDS instance identifier returned earlier to determine the Auto Minor Version Upgrade status for the selected instance:aws rds describe-db-instances --region <regionName> --db-instance-identifier <dbInstanceIdentifier> --query 'DBInstances[*].AutoMinorVersionUpgrade'4. The command output should return the feature current status. If the current status is set totrue, the feature is enabled and the minor engine upgrades will be applied to the selected RDS instance.- Assessment Status
Automated
- Rationale Statement
AWS RDS will occasionally deprecate minor engine versions and provide new ones for an upgrade. When the last version number within the release is replaced, the version changed is considered minor. With Auto Minor Version Upgrade feature enabled, the version upgrades will occur automatically during the specified maintenance window so your RDS instances can get the new features, bug fixes, and security patches for their database engines.
- Remediation Procedure
From Console: 1. Log in to the AWS management console and navigate to the RDS dashboard at https://console.aws.amazon.com/rds/. 2. In the left navigation panel, click on
Databases. 3. Select the RDS instance that wants to update. 4. Click on theModifybutton placed on the top right side. 5. On theModify DB Instance: <instance identifier>page, In theMaintenancesection, selectAuto minor version upgradeclick on theYesradio button. 6. At the bottom of the page click onContinue, check to Apply Immediately to apply the changes immediately, or selectApply during the next scheduled maintenance windowto avoid any downtime. 7. Review the changes and click onModify DB Instance. The instance status should change from available to modifying and back to available. Once the feature is enabled, theAuto Minor Version Upgradestatus should change toYes. From Command Line: 1. Rundescribe-db-instancescommand to list all RDS database instance names, available in the selected AWS region:aws rds describe-db-instances --region <regionName> --query 'DBInstances[*].DBInstanceIdentifier'2. The command output should return each database instance identifier. 3. Run themodify-db-instancecommand to modify the selected RDS instance configuration this command will apply the changes immediately, Remove--apply-immediatelyto apply changes during the next scheduled maintenance window and avoid any downtime:aws rds modify-db-instance --region <regionName> --db-instance-identifier <dbInstanceIdentifier> --auto-minor-version-upgrade --apply-immediately4. The command output should reveal the new configuration metadata for the RDS instance and checkAutoMinorVersionUpgradeparameter value. 5. Rundescribe-db-instancescommand to check if the Auto Minor Version Upgrade feature has been successfully enable:aws rds describe-db-instances --region <regionName> --db-instance-identifier <dbInstanceIdentifier> --query 'DBInstances[*].AutoMinorVersionUpgrade'6. The command output should return the feature current status set totrue, the feature isenabledand the minor engine upgrades will be applied to the selected RDS instance.
2.3.3Ensure that public access is not given to RDS Instance1
Attributes
- Profile
Level 1
- Section
2 Storage
- References
- https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/UsingWithRDS.html:https://docs.aws.amazon.com/vpc/latest/userguide/VPC_Scenario2.html:https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_VPC.WorkingWithRDSInstanceinaVPC.html:https://aws.amazon.com/rds/faqs/
- Sub Section
2.3 Relational Database Service (RDS)
- Description
Ensure and verify that RDS database instances provisioned in your AWS account do restrict unauthorized access in order to minimize security risks. To restrict access to anypublicly accessible RDS database instance, you must disable the database PubliclyAccessible flag and update the VPC security group associated with the instance
- Audit Procedure
From Console: 1. Log in to the AWS management console and navigate to the RDS dashboard at https://console.aws.amazon.com/rds/. 2. Under the navigation panel, On RDS Dashboard, click Databases. 3. Select the RDS instance that you want to examine. 4. Click Instance Name from the dashboard, Under `Connectivity and Security. 5. On the Security, check if the Publicly Accessible flag status is set to Yes, follow the below-mentioned steps to check database subnet access. • In the networking section, click the subnet link available under Subnets • The link will redirect you to the VPC Subnets page. • Select the subnet listed on the page and click the Route Table tab from the dashboard bottom panel. If the route table contains any entries with the destination CIDR block set to 0.0.0.0/0 and with an Internet Gateway attached. • The selected RDS database instance was provisioned inside a public subnet, therefore is not running within a logically isolated environment and can be accessible from the Internet. 6. Repeat steps no. 4 and 5 to determine the type (public or private) and subnet for other RDS database instances provisioned in the current region. 7. Change the AWS region from the navigation bar and repeat the audit process for other regions. From Command Line: 1. Run describe-db-instances command to list all RDS database names, available in the selected AWS region: aws rds describe-db-instances --region <region-name> --query 'DBInstances[].DBInstanceIdentifier' 2. The command output should return each database instance identifier. 3. Run again describe-db-instances command using the PubliclyAccessible parameter as query filter to reveal the database instance Publicly Accessible flag status: aws rds describe-db-instances --region <region-name> --db-instance-identifier <db-instance-name> --query 'DBInstances[].PubliclyAccessible' 4. Check for the Publicly Accessible parameter status, If the Publicly Accessible flag is set to Yes. Then selected RDS database instance is publicly accessible and insecure, follow the below-mentioned steps to check database subnet access 5. Run again describe-db-instances command using the RDS database instance identifier that you want to check and appropriate filtering to describe the VPC subnet(s) associated with the selected instance: aws rds describe-db-instances --region <region-name> --db-instance-identifier <db-name> --query 'DBInstances[].DBSubnetGroup.Subnets[]' • The command output should list the subnets available in the selected database subnet group. 6. Run describe-route-tables command using the ID of the subnet returned at the previous step to describe the routes of the VPC route table associated with the selected subnet: aws ec2 describe-route-tables --region <region-name> --filters 'Name=association.subnet-id,Values=<SubnetID>' --query 'RouteTables[].Routes[]' • If the command returns the route table associated with database instance subnet ID. Check the GatewayId and DestinationCidrBlock attributes values returned in the output. If the route table contains any entries with the GatewayId value set to igw-xxxxxxxx and the DestinationCidrBlock value set to 0.0.0.0/0, the selected RDS database instance was provisioned inside a public subnet. • Or • If the command returns empty results, the route table is implicitly associated with subnet, therefore the audit process continues with the next step 7. Run again describe-db-instances command using the RDS database instance identifier that you want to check and appropriate filtering to describe the VPC ID associated with the selected instance: aws rds describe-db-instances --region <region-name> --db-instance-identifier <db-name> --query 'DBInstances[].DBSubnetGroup.VpcId' • The command output should show the VPC ID in the selected database subnet group 8. Now run describe-route-tables command using the ID of the VPC returned at the previous step to describe the routes of the VPC main route table implicitly associated with the selected subnet: aws ec2 describe-route-tables --region <region-name> --filters 'Name=vpc- id,Values=<VPC-ID>' 'Name=association.main,Values=true' --query 'RouteTables[].Routes[]' • The command output returns the VPC main route table implicitly associated with database instance subnet ID. Check the GatewayId and DestinationCidrBlock attributes values returned in the output. If the route table contains any entries with the GatewayId value set to igw-xxxxxxxx and the DestinationCidrBlock value set to 0.0.0.0/0, the selected RDS database instance was provisioned inside a public subnet, therefore is not running within a logically isolated environment and does not adhere to AWS security best practices.
- Assessment Status
Automated
- Rationale Statement
Ensure that no public-facing RDS database instances are provisioned in your AWS account and restrict unauthorized access in order to minimize security risks. When the RDS instance allows unrestricted access (0.0.0.0/0), everyone and everything on the Internet can establish a connection to your database and this can increase the opportunity for malicious activities such as brute force attacks, PostgreSQL injections, or DoS/DDoS attacks.
- Remediation Procedure
From Console: 1. Log in to the AWS management console and navigate to the RDS dashboard at https://console.aws.amazon.com/rds/. 2. Under the navigation panel, On RDS Dashboard, click Databases. 3. Select the RDS instance that you want to update. 4. Click Modify from the dashboard top menu. 5. On the Modify DB Instance panel, under the Connectivity section, click on Additional connectivity configuration and update the value for Publicly Accessible to Not publicly accessible to restrict public access. Follow the below steps to update subnet configurations: • Select the Connectivity and security tab, and click on the VPC attribute value inside the Networking section. • Select the Details tab from the VPC dashboard bottom panel and click on Route table configuration attribute value. • On the Route table details page, select the Routes tab from the dashboard bottom panel and click on Edit routes. • On the Edit routes page, update the Destination of Target which is set to igw- xxxxx and click on Save routes. 6. On the Modify DB Instance panel Click on Continue and In the Scheduling of modifications section, perform one of the following actions based on your requirements: • Select Apply during the next scheduled maintenance window to apply the changes automatically during the next scheduled maintenance window. • Select Apply immediately to apply the changes right away. With this option, any pending modifications will be asynchronously applied as soon as possible, regardless of the maintenance window setting for this RDS database instance. Note that any changes available in the pending modifications queue are also applied. If any of the pending modifications require downtime, choosing this option can cause unexpected downtime for the application. 7. Repeat steps 3 to 6 for each RDS instance available in the current region. 8. Change the AWS region from the navigation bar to repeat the process for other regions. From Command Line: 1. Run describe-db-instances command to list all RDS database names identifiers, available in the selected AWS region: aws rds describe-db-instances --region <region-name> --query 'DBInstances[*].DBInstanceIdentifier' 2. The command output should return each database instance identifier. 3. Run modify-db-instance command to modify the selected RDS instance configuration. Then use the following command to disable the Publicly Accessible flag for the selected RDS instances. This command use the apply- immediately flag. If you want to avoid any downtime --no-apply-immediately flag can be used: aws rds modify-db-instance --region <region-name> --db-instance-identifier <db-name> --no-publicly-accessible --apply-immediately 4. The command output should reveal the PubliclyAccessible configuration under pending values and should get applied at the specified time. 5. Updating the Internet Gateway Destination via AWS CLI is not currently supported To update information about Internet Gateway use the AWS Console Procedure. 6. Repeat steps 1 to 5 for each RDS instance provisioned in the current region. 7. Change the AWS region by using the --region filter to repeat the process for other regions.
2.4.1Ensure that encryption is enabled for EFS file systems1
Attributes
- Profile
Level 1
- Section
2 Storage
- Sub Section
2.4 Elastic File System (EFS)
- Description
EFS data should be encrypted at rest using AWS KMS (Key Management Service).
- Audit Procedure
From Console: 1. Login to the AWS Management Console and Navigate to
Elastic File System (EFS) dashboard. 2. SelectFile Systemsfrom the left navigation panel. 3. Each item on the list has a visible Encrypted field that displays data at rest encryption status. 4. Validate that this field readsEncryptedfor all EFS file systems in all AWS regions. **From CLI:** 1. Run describe-file-systems command using custom query filters to list the identifiers of all AWS EFS file systems currently available within the selected region: ``` aws efs describe-file-systems --region <region> --output table --query 'FileSystems[*].FileSystemId' ``` 2. The command output should return a table with the requested file system IDs. 3. Run describe-file-systems command using the ID of the file system that you want to examine as identifier and the necessary query filters: ``` aws efs describe-file-systems --region <region> --file-system-id <file-system-id from step 2 output> --query 'FileSystems[*].Encrypted' ``` 4. The command output should return the file system encryption status true or false. If the returned value isfalse, the selected AWS EFS file system is not encrypted and if the returned value istrue`, the selected AWS EFS file system is encrypted.- Assessment Status
Automated
- Rationale Statement
Data should be encrypted at rest to reduce the risk of a data breach via direct access to the storage device.
- Remediation Procedure
It is important to note that EFS file system data at rest encryption must be turned on when creating the file system. If an EFS file system has been created without data at rest encryption enabled then you must create another EFS file system with the correct configuration and transfer the data. Steps to create an EFS file system with data encrypted at rest: From Console: 1. Login to the AWS Management Console and Navigate to
Elastic File System (EFS)dashboard. 2. SelectFile Systemsfrom the left navigation panel. 3. ClickCreate File Systembutton from the dashboard top menu to start the file system setup process. 4. On theConfigure file system accessconfiguration page, perform the following actions. - Choose the right VPC from the VPC dropdown list. - Within Create mount targets section, select the checkboxes for all of the Availability Zones (AZs) within the selected VPC. These will be your mount targets. - ClickNext stepto continue. 5. Perform the following on theConfigure optional settingspage. - Createtagsto describe your new file system. - Chooseperformance modebased on your requirements. - CheckEnable encryptioncheckbox and chooseaws/elasticfilesystemfrom Select KMS master key dropdown list to enable encryption for the new file system using the default master key provided and managed by AWS KMS. - ClickNext stepto continue. 6. Review the file system configuration details on thereview and createpage and then clickCreate File Systemto create your new AWS EFS file system. 7. Copy the data from the old unencrypted EFS file system onto the newly create encrypted file system. 8. Remove the unencrypted file system as soon as your data migration to the newly create encrypted file system is completed. 9. Change the AWS region from the navigation bar and repeat the entire process for other aws regions. From CLI: 1. Run describe-file-systems command to describe the configuration information available for the selected (unencrypted) file system (see Audit section to identify the right resource):aws efs describe-file-systems --region <region> --file-system-id <file-system-id from audit section step 2 output>2. The command output should return the requested configuration information. 3. To provision a new AWS EFS file system, you need to generate a universally unique identifier (UUID) in order to create the token required by the create-file-system command. To create the required token, you can use a randomly generated UUID from "https://www.uuidgenerator.net". 4. Run create-file-system command using the unique token created at the previous step.aws efs create-file-system --region <region> --creation-token <Token (randomly generated UUID from step 3)> --performance-mode generalPurpose --encrypted5. The command output should return the new file system configuration metadata. 6. Run create-mount-target command using the newly created EFS file system ID returned at the previous step as identifier and the ID of the Availability Zone (AZ) that will represent the mount target:aws efs create-mount-target --region <region> --file-system-id <file-system-id> --subnet-id <subnet-id>7. The command output should return the new mount target metadata. 8. Now you can mount your file system from an EC2 instance. 9. Copy the data from the old unencrypted EFS file system onto the newly create encrypted file system. 10. Remove the unencrypted file system as soon as your data migration to the newly create encrypted file system is completed.aws efs delete-file-system --region <region> --file-system-id <unencrypted-file-system-id>11. Change the AWS region by updating the --region and repeat the entire process for other aws regions.
3 Logging99
3.1Ensure CloudTrail is enabled in all regions1
Attributes
- Profile
Level 1
- Section
3 Logging
- Description
AWS CloudTrail is a web service that records AWS API calls for your account and delivers log files to you. The recorded information includes the identity of the API caller, the time of the API call, the source IP address of the API caller, the request parameters, and the response elements returned by the AWS service. CloudTrail provides a history of AWS API calls for an account, including API calls made via the Management Console, SDKs, command line tools, and higher-level AWS services (such as CloudFormation).
- Audit Procedure
Perform the following to determine if CloudTrail is enabled for all regions: From Console: 1. Sign in to the AWS Management Console and open the CloudTrail console at https://console.aws.amazon.com/cloudtrail 2. Click on
Trailson the left navigation pane - You will be presented with a list of trails across all regions 3. Ensure at least one Trail hasAllspecified in theRegioncolumn 4. Click on a trail via the link in the Name column 5. EnsureLoggingis set toON6. EnsureApply trail to all regionsis set toYes7. In sectionManagement EventsensureRead/Write Eventsset toALLFrom Command Line:aws cloudtrail describe-trailsEnsureIsMultiRegionTrailis set totrueaws cloudtrail get-trail-status --name <trailname shown in describe-trails>EnsureIsLoggingis set totrueaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll- Impact Statement
S3 lifecycle features can be used to manage the accumulation and management of logs over time. See the following AWS resource for more information on these features: 1. https://docs.aws.amazon.com/AmazonS3/latest/dev/object-lifecycle-mgmt.html
- Assessment Status
Automated
- Rationale Statement
The AWS API call history produced by CloudTrail enables security analysis, resource change tracking, and compliance auditing. Additionally, - ensuring that a multi-regions trail exists will ensure that unexpected activity occurring in otherwise unused regions is detected - ensuring that a multi-regions trail exists will ensure that
Global Service Loggingis enabled for a trail by default to capture recording of events generated on AWS global services - for a multi-regions trail, ensuring that management events configured for all type of Read/Writes ensures recording of management operations that are performed on all resources in an AWS account- Remediation Procedure
Perform the following to enable global (Multi-region) CloudTrail logging: From Console: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/cloudtrail 2. Click on Trails on the left navigation pane 3. Click
Get Started Now, if presented - ClickAdd new trail- Enter a trail name in theTrail namebox - Set theApply trail to all regionsoption toYes- Specify an S3 bucket name in theS3 bucketbox - ClickCreate4. If 1 or more trails already exist, select the target trail to enable for global logging 5. Click the edit icon (pencil) next toApply trail to all regions, ClickYesand ClickSave. 6. Click the edit icon (pencil) next toManagement EventsclickAllfor settingRead/Write Eventsand ClickSave. From Command Line:aws cloudtrail create-trail --name <trail_name> --bucket-name <s3_bucket_for_cloudtrail> --is-multi-region-trail aws cloudtrail update-trail --name <trail_name> --is-multi-region-trailNote: Creating CloudTrail via CLI without providing any overriding options configuresManagement Eventsto setAlltype ofRead/Writesby default.
3.2Ensure CloudTrail log file validation is enabled1
Attributes
- Profile
Level 2
- Section
3 Logging
- Description
CloudTrail log file validation creates a digitally signed digest file containing a hash of each log that CloudTrail writes to S3. These digest files can be used to determine whether a log file was changed, deleted, or unchanged after CloudTrail delivered the log. It is recommended that file validation be enabled on all CloudTrails.
- Audit Procedure
Perform the following on each trail to determine if log file validation is enabled: From Console: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/cloudtrail 2. Click on
Trailson the left navigation pane 3. For Every Trail: - Click on a trail via the link in the Name column - Under theGeneral detailssection, ensureLog file validationis set toEnabledFrom Command Line:aws cloudtrail describe-trailsEnsureLogFileValidationEnabledis set totruefor each trail- Assessment Status
Automated
- Rationale Statement
Enabling log file validation will provide additional integrity checking of CloudTrail logs.
- Remediation Procedure
Perform the following to enable log file validation on a given trail: From Console: 1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/cloudtrail 2. Click on
Trailson the left navigation pane 3. Click on target trail 4. Within theGeneral detailssection clickedit5. Under theAdvanced settingssection 6. Check the enable box underLog file validation7. ClickSave changesFrom Command Line:aws cloudtrail update-trail --name <trail_name> --enable-log-file-validationNote that periodic validation of logs using these digests can be performed by running the following command:aws cloudtrail validate-logs --trail-arn <trail_arn> --start-time <start_time> --end-time <end_time>
3.3Ensure AWS Config is enabled in all regions1
Attributes
- Profile
Level 2
- Section
3 Logging
- Description
AWS Config is a web service that performs configuration management of supported AWS resources within your account and delivers log files to you. The recorded information includes the configuration item (AWS resource), relationships between configuration items (AWS resources), any configuration changes between resources. It is recommended AWS Config be enabled in all regions.
- Audit Procedure
Process to evaluate AWS Config configuration per region From Console: 1. Sign in to the AWS Management Console and open the AWS Config console at https://console.aws.amazon.com/config/. 2. On the top right of the console select target Region. 3. If presented with Setup AWS Config - follow remediation procedure: 4. On the Resource inventory page, Click on edit (the gear icon). The Set Up AWS Config page appears. 5. Ensure 1 or both check-boxes under "All Resources" is checked. - Include global resources related to IAM resources - which needs to be enabled in 1 region only 6. Ensure the correct S3 bucket has been defined. 7. Ensure the correct SNS topic has been defined. 8. Repeat steps 2 to 7 for each region. From Command Line: 1. Run this command to show all AWS Config recorders and their properties:
aws configservice describe-configuration-recorders2. Evaluate the output to ensure that there's at least one recorder for whichrecordingGroupobject includes"allSupported": trueAND"includeGlobalResourceTypes": trueNote: There is one more parameter "ResourceTypes" in recordingGroup object. We don't need to check the same as whenever we set "allSupported": true, AWS enforces resource types to be empty ("ResourceTypes":[]) Sample Output:{ "ConfigurationRecorders": [ { "recordingGroup": { "allSupported": true, "resourceTypes": [], "includeGlobalResourceTypes": true }, "roleARN": "arn:aws:iam::<AWS_Account_ID>:role/service-role/<config-role-name>", "name": "default" } ] }3. Run this command to show the status for all AWS Config recorders:aws configservice describe-configuration-recorder-status4. In the output, find recorders withnamekey matching the recorders that met criteria in step 2. Ensure that at least one of them includes"recording": trueand"lastStatus": "SUCCESS"- Impact Statement
It is recommended AWS Config be enabled in all regions.
- Assessment Status
Automated
- Rationale Statement
The AWS configuration item history captured by AWS Config enables security analysis, resource change tracking, and compliance auditing.
- Remediation Procedure
To implement AWS Config configuration: From Console: 1. Select the region you want to focus on in the top right of the console 2. Click
Services3. ClickConfig4. Define which resources you want to record in the selected region 5. Choose to include global resources (IAM resources) 6. Specify an S3 bucket in the same account or in another managed AWS account 7. Create an SNS Topic from the same AWS account or another managed AWS account From Command Line: 1. Ensure there is an appropriate S3 bucket, SNS topic, and IAM role per the AWS Config Service prerequisites. 2. Run this command to set up the configuration recorderaws configservice subscribe --s3-bucket my-config-bucket --sns-topic arn:aws:sns:us-east-1:012345678912:my-config-notice --iam-role arn:aws:iam::012345678912:role/myConfigRole3. Run this command to start the configuration recorder:start-configuration-recorder --configuration-recorder-name <value>
3.4Ensure S3 bucket access logging is enabled on the CloudTrail S3 bucket1
Attributes
- Profile
Level 1
- Section
3 Logging
- Description
S3 Bucket Access Logging generates a log that contains access records for each request made to your S3 bucket. An access log record contains details about the request, such as the request type, the resources specified in the request worked, and the time and date the request was processed. It is recommended that bucket access logging be enabled on the CloudTrail S3 bucket.
- Audit Procedure
Perform the following ensure the CloudTrail S3 bucket has access logging is enabled: From Console: 1. Go to the Amazon CloudTrail console at https://console.aws.amazon.com/cloudtrail/home 2. In the API activity history pane on the left, click Trails 3. In the Trails pane, note the bucket names in the S3 bucket column 4. Sign in to the AWS Management Console and open the S3 console at https://console.aws.amazon.com/s3. 5. Under
All Bucketsclick on a target S3 bucket 6. Click onPropertiesin the top right of the console 7. UnderBucket:_<bucket_name>_ click onLogging8. EnsureEnabledis checked. From Command Line: 1. Get the name of the S3 bucket that CloudTrail is logging to:aws cloudtrail describe-trails --query 'trailList[*].S3BucketName'2. Ensure Bucket Logging is enabled:aws s3api get-bucket-logging --bucket <s3_bucket_for_cloudtrail>Ensure command does not returns empty output. Sample Output for a bucket with logging enabled:{ "LoggingEnabled": { "TargetPrefix": "<Prefix_Test>", "TargetBucket": "<Bucket_name_for_Storing_Logs>" } }- Assessment Status
Automated
- Rationale Statement
By enabling S3 bucket logging on target S3 buckets, it is possible to capture all events which may affect objects within any target buckets. Configuring logs to be placed in a separate bucket allows access to log information which can be useful in security and incident response workflows.
- Remediation Procedure
Perform the following to enable S3 bucket logging: From Console: 1. Sign in to the AWS Management Console and open the S3 console at https://console.aws.amazon.com/s3. 2. Under
All Bucketsclick on the target S3 bucket 3. Click onPropertiesin the top right of the console 4. UnderBucket:<s3_bucket_for_cloudtrail> click onLogging5. Configure bucket logging - Click on theEnabledcheckbox - Select Target Bucket from list - Enter a Target Prefix 6. ClickSave. From Command Line: 1. Get the name of the S3 bucket that CloudTrail is logging to:aws cloudtrail describe-trails --region <region-name> --query trailList[*].S3BucketName2. Copy and add target bucket name at<Logging_BucketName>, Prefix for logfile at<LogFilePrefix>and optionally add an email address in the following template and save it as<FileName.Json>:{ "LoggingEnabled": { "TargetBucket": "<Logging_BucketName>", "TargetPrefix": "<LogFilePrefix>", "TargetGrants": [ { "Grantee": { "Type": "AmazonCustomerByEmail", "EmailAddress": "<EmailID>" }, "Permission": "FULL_CONTROL" } ] } }3. Run theput-bucket-loggingcommand with bucket name and<FileName.Json>as input, for more information refer at put-bucket-logging:aws s3api put-bucket-logging --bucket <BucketName> --bucket-logging-status file://<FileName.Json>
3.5Ensure CloudTrail logs are encrypted at rest using KMS CMKs1
Attributes
- Profile
Level 2
- Section
3 Logging
- Description
AWS CloudTrail is a web service that records AWS API calls for an account and makes those logs available to users and resources in accordance with IAM policies. AWS Key Management Service (KMS) is a managed service that helps create and control the encryption keys used to encrypt account data, and uses Hardware Security Modules (HSMs) to protect the security of encryption keys. CloudTrail logs can be configured to leverage server side encryption (SSE) and KMS customer created master keys (CMK) to further protect CloudTrail logs. It is recommended that CloudTrail be configured to use SSE-KMS.
- Audit Procedure
Perform the following to determine if CloudTrail is configured to use SSE-KMS: From Console: 1. Sign in to the AWS Management Console and open the CloudTrail console at https://console.aws.amazon.com/cloudtrail 2. In the left navigation pane, choose
Trails. 3. Select a Trail 4. Under theS3section, ensureEncrypt log filesis set toYesand a KMS key ID is specified in theKSM Key Idfield. From Command Line: 1. Run the following command:aws cloudtrail describe-trails2. For each trail listed, SSE-KMS is enabled if the trail has aKmsKeyIdproperty defined.- Impact Statement
Customer created keys incur an additional cost. See https://aws.amazon.com/kms/pricing/ for more information.
- Assessment Status
Automated
- Rationale Statement
Configuring CloudTrail to use SSE-KMS provides additional confidentiality controls on log data as a given user must have S3 read permission on the corresponding log bucket and must be granted decrypt permission by the CMK policy.
- Remediation Procedure
Perform the following to configure CloudTrail to use SSE-KMS: From Console: 1. Sign in to the AWS Management Console and open the CloudTrail console at https://console.aws.amazon.com/cloudtrail 2. In the left navigation pane, choose
Trails. 3. Click on a Trail 4. Under theS3section click on the edit button (pencil icon) 5. ClickAdvanced6. Select an existing CMK from theKMS key Iddrop-down menu - Note: Ensure the CMK is located in the same region as the S3 bucket - Note: You will need to apply a KMS Key policy on the selected CMK in order for CloudTrail as a service to encrypt and decrypt log files using the CMK provided. Steps are provided here for editing the selected CMK Key policy 7. ClickSave8. You will see a notification message stating that you need to have decrypt permissions on the specified KMS key to decrypt log files. 9. ClickYesFrom Command Line:aws cloudtrail update-trail --name <trail_name> --kms-id <cloudtrail_kms_key> aws kms put-key-policy --key-id <cloudtrail_kms_key> --policy <cloudtrail_kms_key_policy>- Additional Information
3 statements which need to be added to the CMK policy: 1. Enable Cloudtrail to describe CMK properties
<pre class="programlisting" style="font-style: normal;">{ "Sid": "Allow CloudTrail access", "Effect": "Allow", "Principal": { "Service": "cloudtrail.amazonaws.com" }, "Action": "kms:DescribeKey", "Resource": "*" }2. Granting encrypt permissions<pre class="programlisting" style="font-style: normal;">{ "Sid": "Allow CloudTrail to encrypt logs", "Effect": "Allow", "Principal": { "Service": "cloudtrail.amazonaws.com" }, "Action": "kms:GenerateDataKey*", "Resource": "*", "Condition": { "StringLike": { "kms:EncryptionContext:aws:cloudtrail:arn": [ "arn:aws:cloudtrail:*:aws-account-id:trail/*" ] } } }3. Granting decrypt permissions<pre class="programlisting" style="font-style: normal;">{ "Sid": "Enable CloudTrail log decrypt permissions", "Effect": "Allow", "Principal": { "AWS": "arn:aws:iam::aws-account-id:user/username" }, "Action": "kms:Decrypt", "Resource": "*", "Condition": { "Null": { "kms:EncryptionContext:aws:cloudtrail:arn": "false" } } }
3.6Ensure rotation for customer created symmetric CMKs is enabled1
Attributes
- Profile
Level 2
- Section
3 Logging
- Description
AWS Key Management Service (KMS) allows customers to rotate the backing key which is key material stored within the KMS which is tied to the key ID of the Customer Created customer master key (CMK). It is the backing key that is used to perform cryptographic operations such as encryption and decryption. Automated key rotation currently retains all prior backing keys so that decryption of encrypted data can take place transparently. It is recommended that CMK key rotation be enabled for symmetric keys. Key rotation can not be enabled for any asymmetric CMK.
- Audit Procedure
From Console: 1. Sign in to the AWS Management Console and open the KMS console at: https://console.aws.amazon.com/kms. 2. In the left navigation pane, click Customer-managed keys. 3. Select a customer managed CMK where Key spec = SYMMETRIC_DEFAULT. 4. Select the Key rotation tab. 5. Ensure the Automatically rotate this KMS key every year checkbox is checked. 6. Repeat steps 3–5 for all customer-managed CMKs where 'Key spec = SYMMETRIC_DEFAULT'.
- Impact Statement
Creation, management, and storage of CMKs may require additional time from and administrator.
- Assessment Status
Automated
- Rationale Statement
Rotating encryption keys helps reduce the potential impact of a compromised key as data encrypted with a new key cannot be accessed with a previous key that may have been exposed. Keys should be rotated every year, or upon event that would result in the compromise of that key.
- Remediation Procedure
From Console: 1. Sign in to the AWS Management Console and open the KMS console at: https://console.aws.amazon.com/kms. 2. In the left navigation pane, click Customer-managed keys. 3. Select a key where Key spec = SYMMETRIC_DEFAULT that does not have automatic rotation enabled. 4. Select the Key rotation tab. 5. Check the Automatically rotate this KMS key every year checkbox. 6. Click Save. 7. Repeat steps 3–6 for all customer-managed CMKs that do not have automatic rotation enabled.
3.7Ensure VPC flow logging is enabled in all VPCs1
Attributes
- Profile
Level 2
- Section
3 Logging
- Description
VPC Flow Logs is a feature that enables you to capture information about the IP traffic going to and from network interfaces in your VPC. After you've created a flow log, you can view and retrieve its data in Amazon CloudWatch Logs. It is recommended that VPC Flow Logs be enabled for packet "Rejects" for VPCs.
- Audit Procedure
Perform the following to determine if VPC Flow logs are enabled: From Console: 1. Sign into the management console 2. Select
ServicesthenVPC3. In the left navigation pane, selectYour VPCs4. Select a VPC 5. In the right pane, select theFlow Logstab. 6. Ensure a Log Flow exists that hasActivein theStatuscolumn. From Command Line: 1. Rundescribe-vpcscommand (OSX/Linux/UNIX) to list the VPC networks available in the current AWS region:aws ec2 describe-vpcs --region <region> --query Vpcs[].VpcId2. The command output returns theVpcIdavailable in the selected region. 3. Rundescribe-flow-logscommand (OSX/Linux/UNIX) using the VPC ID to determine if the selected virtual network has the Flow Logs feature enabled:aws ec2 describe-flow-logs --filter "Name=resource-id,Values=<vpc-id>"4. If there are no Flow Logs created for the selected VPC, the command output will return anempty list []. 5. Repeat step 3 for other VPCs available in the same region. 6. Change the region by updating--regionand repeat steps 1 - 5 for all the VPCs.- Impact Statement
By default, CloudWatch Logs will store Logs indefinitely unless a specific retention period is defined for the log group. When choosing the number of days to retain, keep in mind the average days it takes an organization to realize they have been breached is 210 days (at the time of this writing). Since additional time is required to research a breach, a minimum 365 day retention policy allows time for detection and research. You may also wish to archive the logs to a cheaper storage service rather than simply deleting them. See the following AWS resource to manage CloudWatch Logs retention periods: 1. https://docs.aws.amazon.com/AmazonCloudWatch/latest/DeveloperGuide/SettingLogRetention.html
- Assessment Status
Automated
- Rationale Statement
VPC Flow Logs provide visibility into network traffic that traverses the VPC and can be used to detect anomalous traffic or insight during security workflows.
- Remediation Procedure
Perform the following to determine if VPC Flow logs is enabled: From Console: 1. Sign into the management console 2. Select
ServicesthenVPC3. In the left navigation pane, selectYour VPCs4. Select a VPC 5. In the right pane, select theFlow Logstab. 6. If no Flow Log exists, clickCreate Flow Log7. For Filter, selectReject8. Enter in aRoleandDestination Log Group9. ClickCreate Log Flow10. Click onCloudWatch Logs GroupNote: Setting the filter to "Reject" will dramatically reduce the logging data accumulation for this recommendation and provide sufficient information for the purposes of breach detection, research and remediation. However, during periods of least privilege security group engineering, setting this the filter to "All" can be very helpful in discovering existing traffic flows required for proper operation of an already running environment. From Command Line: 1. Create a policy document and name it asrole_policy_document.jsonand paste the following content:{ "Version": "2012-10-17", "Statement": [ { "Sid": "test", "Effect": "Allow", "Principal": { "Service": "ec2.amazonaws.com" }, "Action": "sts:AssumeRole" } ] }2. Create another policy document and name it asiam_policy.jsonand paste the following content:{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action":[ "logs:CreateLogGroup", "logs:CreateLogStream", "logs:DescribeLogGroups", "logs:DescribeLogStreams", "logs:PutLogEvents", "logs:GetLogEvents", "logs:FilterLogEvents" ], "Resource": "*" } ] }3. Run the below command to create an IAM role:aws iam create-role --role-name <aws_support_iam_role> --assume-role-policy-document file://<file-path>role_policy_document.json4. Run the below command to create an IAM policy:aws iam create-policy --policy-name <ami-policy-name> --policy-document file://<file-path>iam-policy.json5. Runattach-group-policycommand using the IAM policy ARN returned at the previous step to attach the policy to the IAM role (if the command succeeds, no output is returned):aws iam attach-group-policy --policy-arn arn:aws:iam::<aws-account-id>:policy/<iam-policy-name> --group-name <group-name>6. Rundescribe-vpcsto get the VpcId available in the selected region:aws ec2 describe-vpcs --region <region>7. The command output should return the VPC Id available in the selected region. 8. Runcreate-flow-logsto create a flow log for the vpc:aws ec2 create-flow-logs --resource-type VPC --resource-ids <vpc-id> --traffic-type REJECT --log-group-name <log-group-name> --deliver-logs-permission-arn <iam-role-arn>9. Repeat step 8 for other vpcs available in the selected region. 10. Change the region by updating --region and repeat remediation procedure for other vpcs.
3.8Ensure that Object-level logging for write events is enabled for S3 bucket1
Attributes
- Profile
Level 2
- Section
3 Logging
- Description
S3 object-level API operations such as GetObject, DeleteObject, and PutObject are called data events. By default, CloudTrail trails don't log data events and so it is recommended to enable Object-level logging for S3 buckets.
- Audit Procedure
From Console: 1. Login to the AWS Management Console and navigate to CloudTrail dashboard at https://console.aws.amazon.com/cloudtrail/ 2. In the left panel, click Trails and then click on the CloudTrail Name that you want to examine. 3. Review General details 4. Confirm that Multi-region trail is set to Yes 5. Scroll down to Data events 6. Confirm that it reads: Data Events:S3 Log selector template Log all events If 'basic events selectors' is being used it should read: Data events: S3 Bucket Name: All current and future S3 buckets Write: Enabled 7. Repeat steps 2 to 6 to verify that Multi-region trail and Data events logging of S3 buckets in CloudTrail. If the CloudTrails do not have multi-region and data events configured for S3 refer to the remediation below..
- Assessment Status
Automated
- Rationale Statement
Enabling object-level logging will help you meet data compliance requirements within your organization, perform comprehensive security analysis, monitor specific patterns of user behavior in your AWS account or take immediate actions on any object-level API activity within your S3 Buckets using Amazon CloudWatch Events.
- Remediation Procedure
From Console: 1. Login to the AWS Management Console and navigate to S3 dashboard at https://console.aws.amazon.com/s3/ 2. In the left navigation panel, click buckets and then click on the S3 Bucket Name that you want to examine. 3. Click Properties tab to see in detail bucket configuration. 4. In the AWS Cloud Trail data events' section select the CloudTrail name for the recording activity. You can choose an existing Cloudtrail or create a new one by slicking the Configure in Cloudtrailbutton or navigating to the Cloudtrail console linkhttps://console.aws.amazon.com/cloudtrail/
5. Once the Cloudtrail is selected, Select the data Data Events check box. 6. Select S3 from theData event type drop down. 7. Select Log all events from the Log selector template drop down. 8. Repeat steps 2 to 5 to enable object-level logging of write events for other S3 buckets.
3.9Ensure that Object-level logging for read events is enabled for S3 bucket1
Attributes
- Profile
Level 2
- Section
3 Logging
- Description
S3 object-level API operations such as GetObject, DeleteObject, and PutObject are called data events. By default, CloudTrail trails don't log data events and so it is recommended to enable Object-level logging for S3 buckets.
- Audit Procedure
From Console: 1. Login to the AWS Management Console and navigate to S3 dashboard at
https://console.aws.amazon.com/s3/2. In the left navigation panel, clickbucketsand then click on the S3 Bucket Name that you want to examine. 3. ClickPropertiestab to see in detail bucket configuration. 4. If the current status forObject-levellogging is set toDisabled, then object-level logging of read events for the selected s3 bucket is not set. 5. If the current status forObject-levellogging is set toEnabled, but the Read event check-box is unchecked, then object-level logging of read events for the selected s3 bucket is not set. 6. Repeat steps 2 to 5 to verifyobject-levellogging forreadevents of your other S3 buckets. From Command Line: 1. Rundescribe-trailscommand to list the names of all Amazon CloudTrail trails currently available in the selected AWS region:aws cloudtrail describe-trails --region <region-name> --output table --query trailList[*].Name2. The command output will be table of the requested trail names. 3. Runget-event-selectorscommand using the name of the trail returned at the previous step and custom query filters to determine if Data events logging feature is enabled within the selected CloudTrail trail configuration for s3 bucket resources:aws cloudtrail get-event-selectors --region <region-name> --trail-name <trail-name> --query EventSelectors[*].DataResources[]4. The command output should be an array that contains the configuration of the AWS resource(S3 bucket) defined for the Data events selector. 5. If theget-event-selectorscommand returns an empty array, the Data events are not included into the selected AWS Cloudtrail trail logging configuration, therefore the S3 object-level API operations performed within your AWS account are not recorded. 6. Repeat steps 1 to 5 for auditing each s3 bucket to identify other trails that are missing the capability to log Data events. 7. Change the AWS region by updating the--regioncommand parameter and perform the audit process for other regions.- Assessment Status
Automated
- Rationale Statement
Enabling object-level logging will help you meet data compliance requirements within your organization, perform comprehensive security analysis, monitor specific patterns of user behavior in your AWS account or take immediate actions on any object-level API activity using Amazon CloudWatch Events.
- Remediation Procedure
From Console: 1. Login to the AWS Management Console and navigate to S3 dashboard at
https://console.aws.amazon.com/s3/2. In the left navigation panel, clickbucketsand then click on the S3 Bucket Name that you want to examine. 3. ClickPropertiestab to see in detail bucket configuration. 4. Click on theObject-levellogging setting, enter the CloudTrail name for the recording activity. You can choose an existing Cloudtrail or create a new one by navigating to the Cloudtrail console linkhttps://console.aws.amazon.com/cloudtrail/5. Once the Cloudtrail is selected, check the Read event checkbox, so thatobject-levellogging forReadevents is enabled. 6. Repeat steps 2 to 5 to enableobject-levellogging of read events for other S3 buckets. From Command Line: 1. To enableobject-leveldata events logging for S3 buckets within your AWS account, runput-event-selectorscommand using the name of the trail that you want to reconfigure as identifier:aws cloudtrail put-event-selectors --region <region-name> --trail-name <trail-name> --event-selectors '[{ "ReadWriteType": "ReadOnly", "IncludeManagementEvents":true, "DataResources": [{ "Type": "AWS::S3::Object", "Values": ["arn:aws:s3:::<s3-bucket-name>/"] }] }]'2. The command output will beobject-levelevent trail configuration. 3. If you want to enable it for all buckets at ones then change Values parameter to["arn:aws:s3"]in command given above. 4. Repeat step 1 for each s3 bucket to updateobject-levellogging of read events. 5. Change the AWS region by updating the--regioncommand parameter and perform the process for other regions.
4 Monitoring1616
4.1Ensure a log metric filter and alarm exist for unauthorized API calls1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for unauthorized API calls.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with "Name":note<cloudtrail__name>- From value associated with "CloudWatchLogsLogGroupArn" note <cloudtrail_log_group_name> Example: for CloudWatchLogsLogGroupArn that looks like arn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*, <cloudtrail_log_group_name> would be NewGroup - Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <"Name" as shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>that you captured in step 1: ``` aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>" ``` 3. Ensure the output from the above command contains the following: ``` "filterPattern": "{ ($.errorCode = *UnauthorizedOperation) || ($.errorCode = AccessDenied*) || ($.sourceIPAddress!=delivery.logs.amazonaws.com) || ($.eventName!=HeadBucket) }", ``` 4. Note the "filterName"<unauthorized_api_calls_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<unauthorized_api_calls_metric>captured in step 4. ``` aws cloudwatch describe-alarms --query "MetricAlarms[?MetricName ==unauthorized_api_calls_metric]" ``` 6. Note theAlarmActions` value - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Impact Statement
This alert may be triggered by normal read-only console activities that attempt to opportunistically gather optional information, but gracefully fail if they don't have permissions. If an excessive number of alerts are being generated then an organization may wish to consider adding read access to the limited IAM user permissions simply to quiet the alerts. In some cases doing this may allow the users to actually view some areas of the system - any additional access given should be reviewed for alignment with the original limited IAM user intent.
- Assessment Status
Automated
- Rationale Statement
Monitoring unauthorized API calls will help reveal application errors and may reduce time to detect malicious activity.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for unauthorized API calls and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name "cloudtrail_log_group_name" --filter-name "<unauthorized_api_calls_metric>" --metric-transformations metricName=unauthorized_api_calls_metric,metricNamespace=CISBenchmark,metricValue=1 --filter-pattern "{ ($.errorCode = "*UnauthorizedOperation") || ($.errorCode = "AccessDenied*") || ($.sourceIPAddress!="delivery.logs.amazonaws.com") || ($.eventName!="HeadBucket") }"Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. Note: Capture the TopicArn displayed when creating the SNS Topic in Step 2. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn from step 2> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name "unauthorized_api_calls_alarm" --metric-name "unauthorized_api_calls_metric" --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace "CISBenchmark" --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.2Ensure a log metric filter and alarm exist for Management Console sign-in without MFA1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for console logins that are not protected by multi-factor authentication (MFA).
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all
CloudTrails:aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi regionCloudTrailis activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>Ensure in the output thatIsLoggingis set toTRUE- Ensure identified Multi-region 'Cloudtrail' captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure in the output there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventName = "ConsoleLogin") && ($.additionalEventData.MFAUsed != "Yes") }"Or (To reduce false positives incase Single Sign-On (SSO) is used in organization):"filterPattern": "{ ($.eventName = "ConsoleLogin") && ($.additionalEventData.MFAUsed != "Yes") && ($.userIdentity.type = "IAMUser") && ($.responseElements.ConsoleLogin = "Success") }"4. Note the<no_mfa_console_signin_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<no_mfa_console_signin_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<no_mfa_console_signin_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring for single-factor console logins will increase visibility into accounts that are not protected by MFA.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for AWS Management Console sign-in without MFA and the
<cloudtrail_log_group_name>taken from audit step 1. Use Command:aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<no_mfa_console_signin_metric>` --metric-transformations metricName= `<no_mfa_console_signin_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventName = "ConsoleLogin") && ($.additionalEventData.MFAUsed != "Yes") }'Or (To reduce false positives incase Single Sign-On (SSO) is used in organization):aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<no_mfa_console_signin_metric>` --metric-transformations metricName= `<no_mfa_console_signin_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventName = "ConsoleLogin") && ($.additionalEventData.MFAUsed != "Yes") && ($.userIdentity.type = "IAMUser") && ($.responseElements.ConsoleLogin = "Success") }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<no_mfa_console_signin_alarm>` --metric-name `<no_mfa_console_signin_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored -Filter pattern set to
{ ($.eventName = "ConsoleLogin") && ($.additionalEventData.MFAUsed != "Yes") && ($.userIdentity.type = "IAMUser") && ($.responseElements.ConsoleLogin = "Success"}reduces false alarms raised when user logs in via SSO account.
4.3Ensure a log metric filter and alarm exist for usage of 'root' account1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for 'root' login attempts.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ $.userIdentity.type = "Root" && $.userIdentity.invokedBy NOT EXISTS && $.eventType != "AwsServiceEvent" }"4. Note the<root_usage_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<root_usage_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<root_usage_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring for 'root' account logins will provide visibility into the use of a fully privileged account and an opportunity to reduce the use of it.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for 'Root' account usage and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name `<cloudtrail_log_group_name>` --filter-name `<root_usage_metric>` --metric-transformations metricName= `<root_usage_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ $.userIdentity.type = "Root" && $.userIdentity.invokedBy NOT EXISTS && $.eventType != "AwsServiceEvent" }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<root_usage_alarm>` --metric-name `<root_usage_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.4Ensure a log metric filter and alarm exist for IAM policy changes1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established changes made to Identity and Access Management (IAM) policies.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{($.eventName=DeleteGroupPolicy)||($.eventName=DeleteRolePolicy)||($.eventName=DeleteUserPolicy)||($.eventName=PutGroupPolicy)||($.eventName=PutRolePolicy)||($.eventName=PutUserPolicy)||($.eventName=CreatePolicy)||($.eventName=DeletePolicy)||($.eventName=CreatePolicyVersion)||($.eventName=DeletePolicyVersion)||($.eventName=AttachRolePolicy)||($.eventName=DetachRolePolicy)||($.eventName=AttachUserPolicy)||($.eventName=DetachUserPolicy)||($.eventName=AttachGroupPolicy)||($.eventName=DetachGroupPolicy)}"4. Note the<iam_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<iam_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<iam_changes_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring changes to IAM policies will help ensure authentication and authorization controls remain intact.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for IAM policy changes and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name `<cloudtrail_log_group_name>` --filter-name `<iam_changes_metric>` --metric-transformations metricName= `<iam_changes_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{($.eventName=DeleteGroupPolicy)||($.eventName=DeleteRolePolicy)||($.eventName=DeleteUserPolicy)||($.eventName=PutGroupPolicy)||($.eventName=PutRolePolicy)||($.eventName=PutUserPolicy)||($.eventName=CreatePolicy)||($.eventName=DeletePolicy)||($.eventName=CreatePolicyVersion)||($.eventName=DeletePolicyVersion)||($.eventName=AttachRolePolicy)||($.eventName=DetachRolePolicy)||($.eventName=AttachUserPolicy)||($.eventName=DetachUserPolicy)||($.eventName=AttachGroupPolicy)||($.eventName=DetachGroupPolicy)}'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<iam_changes_alarm>` --metric-name `<iam_changes_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.5Ensure a log metric filter and alarm exist for CloudTrail configuration changes1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for detecting changes to CloudTrail's configurations.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventName = CreateTrail) || ($.eventName = UpdateTrail) || ($.eventName = DeleteTrail) || ($.eventName = StartLogging) || ($.eventName = StopLogging) }"4. Note the<cloudtrail_cfg_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<cloudtrail_cfg_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<cloudtrail_cfg_changes_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring changes to CloudTrail's configuration will help ensure sustained visibility to activities performed in the AWS account.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for cloudtrail configuration changes and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<cloudtrail_cfg_changes_metric>` --metric-transformations metricName= `<cloudtrail_cfg_changes_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventName = CreateTrail) || ($.eventName = UpdateTrail) || ($.eventName = DeleteTrail) || ($.eventName = StartLogging) || ($.eventName = StopLogging) }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<cloudtrail_cfg_changes_alarm>` --metric-name `<cloudtrail_cfg_changes_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.6Ensure a log metric filter and alarm exist for AWS Management Console authentication failures1
Attributes
- Profile
Level 2
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for failed console authentication attempts.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventName = ConsoleLogin) && ($.errorMessage = "Failed authentication") }"4. Note the<console_signin_failure_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<console_signin_failure_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<console_signin_failure_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring failed console logins may decrease lead time to detect an attempt to brute force a credential, which may provide an indicator, such as source IP, that can be used in other event correlation.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for AWS management Console Login Failures and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<console_signin_failure_metric>` --metric-transformations metricName= `<console_signin_failure_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventName = ConsoleLogin) && ($.errorMessage = "Failed authentication") }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<console_signin_failure_alarm>` --metric-name `<console_signin_failure_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.7Ensure a log metric filter and alarm exist for disabling or scheduled deletion of customer created CMKs1
Attributes
- Profile
Level 2
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for customer created CMKs which have changed state to disabled or scheduled deletion.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{($.eventSource = kms.amazonaws.com) && (($.eventName=DisableKey)||($.eventName=ScheduleKeyDeletion)) }"4. Note the<disable_or_delete_cmk_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<disable_or_delete_cmk_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<disable_or_delete_cmk_changes_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Data encrypted with disabled or deleted keys will no longer be accessible.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for disabled or scheduled for deletion CMK's and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<disable_or_delete_cmk_changes_metric>` --metric-transformations metricName= `<disable_or_delete_cmk_changes_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{($.eventSource = kms.amazonaws.com) && (($.eventName=DisableKey)||($.eventName=ScheduleKeyDeletion)) }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<disable_or_delete_cmk_changes_alarm>` --metric-name `<disable_or_delete_cmk_changes_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.8Ensure a log metric filter and alarm exist for S3 bucket policy changes1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for changes to S3 bucket policies.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventSource = s3.amazonaws.com) && (($.eventName = PutBucketAcl) || ($.eventName = PutBucketPolicy) || ($.eventName = PutBucketCors) || ($.eventName = PutBucketLifecycle) || ($.eventName = PutBucketReplication) || ($.eventName = DeleteBucketPolicy) || ($.eventName = DeleteBucketCors) || ($.eventName = DeleteBucketLifecycle) || ($.eventName = DeleteBucketReplication)) }"4. Note the<s3_bucket_policy_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<s3_bucket_policy_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<s3_bucket_policy_changes_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring changes to S3 bucket policies may reduce time to detect and correct permissive policies on sensitive S3 buckets.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for S3 bucket policy changes and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<s3_bucket_policy_changes_metric>` --metric-transformations metricName= `<s3_bucket_policy_changes_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventSource = s3.amazonaws.com) && (($.eventName = PutBucketAcl) || ($.eventName = PutBucketPolicy) || ($.eventName = PutBucketCors) || ($.eventName = PutBucketLifecycle) || ($.eventName = PutBucketReplication) || ($.eventName = DeleteBucketPolicy) || ($.eventName = DeleteBucketCors) || ($.eventName = DeleteBucketLifecycle) || ($.eventName = DeleteBucketReplication)) }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<s3_bucket_policy_changes_alarm>` --metric-name `<s3_bucket_policy_changes_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.9Ensure a log metric filter and alarm exist for AWS Config configuration changes1
Attributes
- Profile
Level 2
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for detecting changes to CloudTrail's configurations.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventSource = config.amazonaws.com) && (($.eventName=StopConfigurationRecorder)||($.eventName=DeleteDeliveryChannel)||($.eventName=PutDeliveryChannel)||($.eventName=PutConfigurationRecorder)) }"4. Note the<aws_config_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<aws_config_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<aws_config_changes_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring changes to AWS Config configuration will help ensure sustained visibility of configuration items within the AWS account.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for AWS Configuration changes and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<aws_config_changes_metric>` --metric-transformations metricName= `<aws_config_changes_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventSource = config.amazonaws.com) && (($.eventName=StopConfigurationRecorder)||($.eventName=DeleteDeliveryChannel)||($.eventName=PutDeliveryChannel)||($.eventName=PutConfigurationRecorder)) }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<aws_config_changes_alarm>` --metric-name `<aws_config_changes_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.10Ensure a log metric filter and alarm exist for security group changes1
Attributes
- Profile
Level 2
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. Security Groups are a stateful packet filter that controls ingress and egress traffic within a VPC. It is recommended that a metric filter and alarm be established for detecting changes to Security Groups.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventName = AuthorizeSecurityGroupIngress) || ($.eventName = AuthorizeSecurityGroupEgress) || ($.eventName = RevokeSecurityGroupIngress) || ($.eventName = RevokeSecurityGroupEgress) || ($.eventName = CreateSecurityGroup) || ($.eventName = DeleteSecurityGroup) }"4. Note the<security_group_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<security_group_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query "MetricAlarms[?MetricName== '<security_group_changes_metric>']"6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring changes to security group will help ensure that resources and services are not unintentionally exposed.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for security groups changes and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name "<cloudtrail_log_group_name>" --filter-name "<security_group_changes_metric>" --metric-transformations metricName= "<security_group_changes_metric>" ,metricNamespace="CISBenchmark",metricValue=1 --filter-pattern "{ ($.eventName = AuthorizeSecurityGroupIngress) || ($.eventName = AuthorizeSecurityGroupEgress) || ($.eventName = RevokeSecurityGroupIngress) || ($.eventName = RevokeSecurityGroupEgress) || ($.eventName = CreateSecurityGroup) || ($.eventName = DeleteSecurityGroup) }"Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name "<sns_topic_name>"Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn "<sns_topic_arn>" --protocol <protocol_for_sns> --notification-endpoint "<sns_subscription_endpoints>"Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name "<security_group_changes_alarm>" --metric-name "<security_group_changes_metric>" --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace "CISBenchmark" --alarm-actions "<sns_topic_arn>"- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.11Ensure a log metric filter and alarm exist for changes to Network Access Control Lists (NACL)1
Attributes
- Profile
Level 2
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. NACLs are used as a stateless packet filter to control ingress and egress traffic for subnets within a VPC. It is recommended that a metric filter and alarm be established for changes made to NACLs.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventName = CreateNetworkAcl) || ($.eventName = CreateNetworkAclEntry) || ($.eventName = DeleteNetworkAcl) || ($.eventName = DeleteNetworkAclEntry) || ($.eventName = ReplaceNetworkAclEntry) || ($.eventName = ReplaceNetworkAclAssociation) }"4. Note the<nacl_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<nacl_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<nacl_changes_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring changes to NACLs will help ensure that AWS resources and services are not unintentionally exposed.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for NACL changes and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<nacl_changes_metric>` --metric-transformations metricName= `<nacl_changes_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventName = CreateNetworkAcl) || ($.eventName = CreateNetworkAclEntry) || ($.eventName = DeleteNetworkAcl) || ($.eventName = DeleteNetworkAclEntry) || ($.eventName = ReplaceNetworkAclEntry) || ($.eventName = ReplaceNetworkAclAssociation) }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<nacl_changes_alarm>` --metric-name `<nacl_changes_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.12Ensure a log metric filter and alarm exist for changes to network gateways1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. Network gateways are required to send/receive traffic to a destination outside of a VPC. It is recommended that a metric filter and alarm be established for changes to network gateways.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventName = CreateCustomerGateway) || ($.eventName = DeleteCustomerGateway) || ($.eventName = AttachInternetGateway) || ($.eventName = CreateInternetGateway) || ($.eventName = DeleteInternetGateway) || ($.eventName = DetachInternetGateway) }"4. Note the<network_gw_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<network_gw_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<network_gw_changes_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring changes to network gateways will help ensure that all ingress/egress traffic traverses the VPC border via a controlled path.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for network gateways changes and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<network_gw_changes_metric>` --metric-transformations metricName= `<network_gw_changes_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventName = CreateCustomerGateway) || ($.eventName = DeleteCustomerGateway) || ($.eventName = AttachInternetGateway) || ($.eventName = CreateInternetGateway) || ($.eventName = DeleteInternetGateway) || ($.eventName = DetachInternetGateway) }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<network_gw_changes_alarm>` --metric-name `<network_gw_changes_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.13Ensure route table changes are monitored1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. Routing tables are used to route network traffic between subnets and to network gateways. It is recommended that a metric filter and alarm be established for changes to route tables.
- Audit Procedure
If you are using CloudTrails and CloudWatch , perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarmsconfigured:1. Identify the log group name configured for use with active multi-region CloudTrail:• List all CloudTrails: aws cloudtrail describe-trails• Identify Multi region Cloudtrails: Trails with 'IsMultiRegionTrail' set totrue• From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name> would be NewGroup• Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensure IsLogging is set to TRUE• Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail with IncludeManagementEvents setto true and ReadWriteType set to All2. Get a list of all associated metric filters for this <cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name'<cloudtrail_log_group_name>'3. Ensure the output from the above command contains the following:'filterPattern': '{($.eventSource = ec2.amazonaws.com) && ($.eventName =CreateRoute) || ($.eventName = CreateRouteTable) || ($.eventName =ReplaceRoute) || ($.eventName = ReplaceRouteTableAssociation) || ($.eventName= DeleteRouteTable) || ($.eventName = DeleteRoute) || ($.eventName =DisassociateRouteTable) }'4. Note the <route_table_changes_metric> value associated with thefilterPattern found in step 3.5. Get a list of CloudWatch alarms and filter on the <route_table_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName==
<route_table_changes_metric>]'6. Note the AlarmActions value - this will provide the SNS topic ARN value.7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have 'SubscriptionArn' with valid aws ARN.Example of valid 'SubscriptionArn':'arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>'- Assessment Status
Automated
- Rationale Statement
CloudWatch is an AWS native service that allows you to observe and monitor resources and applications. CloudTrail Logs can also be sent to an external Security informationand event management (SIEM) environment for monitoring and alerting.Monitoring changes to route tables will help ensure that all VPC traffic flows through anexpected path and prevent any accidental or intentional modifications that may lead touncontrolled network traffic. An alarm should be triggered every time an AWS API call isperformed to create, replace, delete, or disassociate a Route Table.
- Remediation Procedure
If you are using CloudTrails and CloudWatch, perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for route table changes and the <cloudtrail_log_group_name> taken from audit step 1. aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> -- filter-name
<route_table_changes_metric>--metric-transformations metricName=<route_table_changes_metric>,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventName = CreateRoute) || ($.eventName = CreateRouteTable) || ($.eventName = ReplaceRoute) || ($.eventName = ReplaceRouteTableAssociation) || ($.eventName = DeleteRouteTable) || ($.eventName = DeleteRoute) || ($.eventName = DisassociateRouteTable) }' Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notify aws sns create-topic --name <sns_topic_name> Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2 aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> - -notification-endpoint <sns_subscription_endpoints> Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2 aws cloudwatch put-metric-alarm --alarm-name<route_table_changes_alarm>--metric-name<route_table_changes_metric>--statistic Sum --period 300 - -threshold 1 --comparison-operator GreaterThanOrEqualToThreshold -- evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.14Ensure a log metric filter and alarm exist for VPC changes1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is possible to have more than 1 VPC within an account, in addition it is also possible to create a peer connection between 2 VPCs enabling network traffic to route between VPCs. It is recommended that a metric filter and alarm be established for changes made to VPCs.
- Audit Procedure
Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: 1. Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails:Trails with "IsMultiRegionTrail" set to true- From value associated with CloudWatchLogsLogGroupArn note<cloudtrail_log_group_name>Example: for CloudWatchLogsLogGroupArn that looks likearn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*,<cloudtrail_log_group_name>would beNewGroup- Ensure Identified Multi region CloudTrail is activeaws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>ensureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Eventsaws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset totrueandReadWriteTypeset toAll2. Get a list of all associated metric filters for this<cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventName = CreateVpc) || ($.eventName = DeleteVpc) || ($.eventName = ModifyVpcAttribute) || ($.eventName = AcceptVpcPeeringConnection) || ($.eventName = CreateVpcPeeringConnection) || ($.eventName = DeleteVpcPeeringConnection) || ($.eventName = RejectVpcPeeringConnection) || ($.eventName = AttachClassicLinkVpc) || ($.eventName = DetachClassicLinkVpc) || ($.eventName = DisableVpcClassicLink) || ($.eventName = EnableVpcClassicLink) }"4. Note the<vpc_changes_metric>value associated with thefilterPatternfound in step 3. 5. Get a list of CloudWatch alarms and filter on the<vpc_changes_metric>captured in step 4.aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<vpc_changes_metric>`]'6. Note theAlarmActionsvalue - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topicaws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN.Example of valid "SubscriptionArn": "arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"- Assessment Status
Automated
- Rationale Statement
Monitoring changes to VPC will help ensure VPC traffic flow is not getting impacted.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for VPC changes and the
<cloudtrail_log_group_name>taken from audit step 1.aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<vpc_changes_metric>` --metric-transformations metricName= `<vpc_changes_metric>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventName = CreateVpc) || ($.eventName = DeleteVpc) || ($.eventName = ModifyVpcAttribute) || ($.eventName = AcceptVpcPeeringConnection) || ($.eventName = CreateVpcPeeringConnection) || ($.eventName = DeleteVpcPeeringConnection) || ($.eventName = RejectVpcPeeringConnection) || ($.eventName = AttachClassicLinkVpc) || ($.eventName = DetachClassicLinkVpc) || ($.eventName = DisableVpcClassicLink) || ($.eventName = EnableVpcClassicLink) }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notifyaws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2aws cloudwatch put-metric-alarm --alarm-name `<vpc_changes_alarm>` --metric-name `<vpc_changes_metric>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>- Additional Information
Configuring log metric filter and alarm on Multi-region (global) CloudTrail - ensures that activities from all regions (used as well as unused) are monitored - ensures that activities on all supported global services are monitored - ensures that all management events across all regions are monitored
4.15Ensure a log metric filter and alarm exists for AWS Organizations changes1
Attributes
- Profile
Level 1
- Section
4 Monitoring
- Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs and establishing corresponding metric filters and alarms. It is recommended that a metric filter and alarm be established for AWS Organizations changes made in the master AWS Account.
- Audit Procedure
- Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: - Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
aws cloudtrail describe-trails- Identify Multi region Cloudtrails, Trails with"IsMultiRegionTrail"set to true - From value associated with CloudWatchLogsLogGroupArn note <cloudtrail_log_group_name> Example: for CloudWatchLogsLogGroupArn that looks like arn:aws:logs:<region>:<aws_account_number>:log-group:NewGroup:*, <cloudtrail_log_group_name> would be NewGroup - Ensure Identified Multi region CloudTrail is active:aws cloudtrail get-trail-status --name <Name of a Multi-region CloudTrail>EnsureIsLoggingis set toTRUE- Ensure identified Multi-region Cloudtrail captures all Management Events:aws cloudtrail get-event-selectors --trail-name <trailname shown in describe-trails>- Ensure there is at least one Event Selector for a Trail withIncludeManagementEventsset to true andReadWriteTypeset toAll. 2. Get a list of all associated metric filters for this <cloudtrail_log_group_name>:aws logs describe-metric-filters --log-group-name "<cloudtrail_log_group_name>"3. Ensure the output from the above command contains the following:"filterPattern": "{ ($.eventSource = organizations.amazonaws.com) && (($.eventName = "AcceptHandshake") || ($.eventName = "AttachPolicy") || ($.eventName = "CreateAccount") || ($.eventName = "CreateOrganizationalUnit") || ($.eventName = "CreatePolicy") || ($.eventName = "DeclineHandshake") || ($.eventName = "DeleteOrganization") || ($.eventName = "DeleteOrganizationalUnit") || ($.eventName = "DeletePolicy") || ($.eventName = "DetachPolicy") || ($.eventName = "DisablePolicyType") || ($.eventName = "EnablePolicyType") || ($.eventName = "InviteAccountToOrganization") || ($.eventName = "LeaveOrganization") || ($.eventName = "MoveAccount") || ($.eventName = "RemoveAccountFromOrganization") || ($.eventName = "UpdatePolicy") || ($.eventName = "UpdateOrganizationalUnit")) }"4. Note the<organizations_changes>value associated with the filterPattern found in step 3. 5. Get a list of CloudWatch alarms and filter on the<organizations_changes>captured in step 4:aws cloudwatch describe-alarms --query 'MetricAlarms[?MetricName== `<organizations_changes>`]'6. Note the AlarmActions value - this will provide the SNS topic ARN value. 7. Ensure there is at least one active subscriber to the SNS topic:aws sns list-subscriptions-by-topic --topic-arn <sns_topic_arn>at least one subscription should have "SubscriptionArn" with valid aws ARN. Example of valid "SubscriptionArn":"arn:aws:sns:<region>:<aws_account_number>:<SnsTopicName>:<SubscriptionID>"
- Perform the following to ensure that there is at least one active multi-region CloudTrail with prescribed metric filters and alarms configured: - Identify the log group name configured for use with active multi-region CloudTrail: - List all CloudTrails:
- Assessment Status
Automated
- Rationale Statement
Monitoring AWS Organizations changes can help you prevent any unwanted, accidental or intentional modifications that may lead to unauthorized access or other security breaches. This monitoring technique helps you to ensure that any unexpected changes performed within your AWS Organizations can be investigated and any unwanted changes can be rolled back.
- Remediation Procedure
Perform the following to setup the metric filter, alarm, SNS topic, and subscription: 1. Create a metric filter based on filter pattern provided which checks for AWS Organizations changes and the
<cloudtrail_log_group_name>taken from audit step 1:aws logs put-metric-filter --log-group-name <cloudtrail_log_group_name> --filter-name `<organizations_changes>` --metric-transformations metricName= `<organizations_changes>` ,metricNamespace='CISBenchmark',metricValue=1 --filter-pattern '{ ($.eventSource = organizations.amazonaws.com) && (($.eventName = "AcceptHandshake") || ($.eventName = "AttachPolicy") || ($.eventName = "CreateAccount") || ($.eventName = "CreateOrganizationalUnit") || ($.eventName = "CreatePolicy") || ($.eventName = "DeclineHandshake") || ($.eventName = "DeleteOrganization") || ($.eventName = "DeleteOrganizationalUnit") || ($.eventName = "DeletePolicy") || ($.eventName = "DetachPolicy") || ($.eventName = "DisablePolicyType") || ($.eventName = "EnablePolicyType") || ($.eventName = "InviteAccountToOrganization") || ($.eventName = "LeaveOrganization") || ($.eventName = "MoveAccount") || ($.eventName = "RemoveAccountFromOrganization") || ($.eventName = "UpdatePolicy") || ($.eventName = "UpdateOrganizationalUnit")) }'Note: You can choose your own metricName and metricNamespace strings. Using the same metricNamespace for all Foundations Benchmark metrics will group them together. 2. Create an SNS topic that the alarm will notify:aws sns create-topic --name <sns_topic_name>Note: you can execute this command once and then re-use the same topic for all monitoring alarms. 3. Create an SNS subscription to the topic created in step 2:aws sns subscribe --topic-arn <sns_topic_arn> --protocol <protocol_for_sns> --notification-endpoint <sns_subscription_endpoints>Note: you can execute this command once and then re-use the SNS subscription for all monitoring alarms. 4. Create an alarm that is associated with the CloudWatch Logs Metric Filter created in step 1 and an SNS topic created in step 2:aws cloudwatch put-metric-alarm --alarm-name `<organizations_changes>` --metric-name `<organizations_changes>` --statistic Sum --period 300 --threshold 1 --comparison-operator GreaterThanOrEqualToThreshold --evaluation-periods 1 --namespace 'CISBenchmark' --alarm-actions <sns_topic_arn>
4.16Ensure AWS Security Hub is enabled1
Attributes
- Profile
Level 2
- Section
4 Monitoring
- Description
Security Hub collects security data from across AWS accounts, services, and supported third-party partner products and helps you analyze your security trends and identify the highest priority security issues. When you enable Security Hub, it begins to consume, aggregate, organize, and prioritize findings from AWS services that you have enabled, such as Amazon GuardDuty, Amazon Inspector, and Amazon Macie. You can also enable integrations with AWS partner security products.
- Audit Procedure
The process to evaluate AWS Security Hub configuration per region From Console: 1. Sign in to the AWS Management Console and open the AWS Security Hub console at https://console.aws.amazon.com/securityhub/. 2. On the top right of the console, select the target Region. 3. If presented with the Security Hub > Summary page then Security Hub is set-up for the selected region. 4. If presented with Setup Security Hub or Get Started With Security Hub - follow the online instructions. 5. Repeat steps 2 to 4 for each region.
- Impact Statement
It is recommended AWS Security Hub be enabled in all regions. AWS Security Hub requires AWS Config to be enabled.
- Assessment Status
Automated
- Rationale Statement
AWS Security Hub provides you with a comprehensive view of your security state in AWS and helps you check your environment against security industry standards and best practices - enabling you to quickly assess the security posture across your AWS accounts.
- Remediation Procedure
To grant the permissions required to enable Security Hub, attach the Security Hub managed policy AWSSecurityHubFullAccess to an IAM user, group, or role. Enabling Security Hub From Console: 1. Use the credentials of the IAM identity to sign in to the Security Hub console. 2. When you open the Security Hub console for the first time, choose Enable AWS Security Hub. 3. On the welcome page, Security standards list the security standards that Security Hub supports. 4. Choose Enable Security Hub. From Command Line: 1. Run the enable-security-hub command. To enable the default standards, include
--enable-default-standards.aws securityhub enable-security-hub --enable-default-standards2. To enable the security hub without the default standards, include--no-enable-default-standards.aws securityhub enable-security-hub --no-enable-default-standards
5 Networking615
5.1Ensure no Network ACLs allow ingress from 0.0.0.0/0 to remote server administration ports3
Attributes
- Profile
Level 1
- Section
5 Networking
- Description
The Network Access Control List (NACL) function provide stateless filtering of ingress and egress network traffic to AWS resources. It is recommended that no NACL allows unrestricted ingress access to remote server administration ports, such as SSH to port
22and RDP to port3389.- Audit Procedure
From Console: Perform the following to determine if the account is configured as prescribed: 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. In the left pane, click
Network ACLs3. For each network ACL, perform the following: - Select the network ACL - Click theInbound Rulestab - Ensure no rule exists that has a port range that includes port22,3389, or other remote server administration ports for your environment and has aSourceof0.0.0.0/0and showsALLOWNote: A Port value ofALLor a port range such as0-1024are inclusive of port22,3389, and other remote server administration ports- Assessment Status
Automated
- Rationale Statement
Public access to remote server administration ports, such as 22 and 3389, increases resource attack surface and unnecessarily raises the risk of resource compromise.
- Remediation Procedure
From Console: Perform the following: 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. In the left pane, click
Network ACLs3. For each network ACL to remediate, perform the following: - Select the network ACL - Click theInbound Rulestab - ClickEdit inbound rules- Either A) update the Source field to a range other than 0.0.0.0/0, or, B) ClickDeleteto remove the offending inbound rule - ClickSave
5.2Ensure no security groups allow ingress from 0.0.0.0/0 to remote server administration ports4
Attributes
- Profile
Level 1
- Section
5 Networking
- Description
Security groups provide stateful filtering of ingress and egress network traffic to AWS resources. It is recommended that no security group allows unrestricted ingress access to remote server administration ports, such as SSH to port
22and RDP to port3389.- Audit Procedure
Perform the following to determine if the account is configured as prescribed: 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. In the left pane, click
Security Groups3. For each security group, perform the following: 1. Select the security group 2. Click theInbound Rulestab 3. Ensure no rule exists that has a port range that includes port22,3389, or other remote server administration ports for your environment and has aSourceof0.0.0.0/0Note: A Port value ofALLor a port range such as0-1024are inclusive of port22,3389, and other remote server administration ports.- Impact Statement
When updating an existing environment, ensure that administrators have access to remote server administration ports through another mechanism before removing access by deleting the 0.0.0.0/0 inbound rule.
- Assessment Status
Automated
- Rationale Statement
Public access to remote server administration ports, such as 22 and 3389, increases resource attack surface and unnecessarily raises the risk of resource compromise.
- Remediation Procedure
Perform the following to implement the prescribed state: 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. In the left pane, click
Security Groups3. For each security group, perform the following: 1. Select the security group 2. Click theInbound Rulestab 3. Click theEdit inbound rulesbutton 4. Identify the rules to be edited or removed 5. Either A) update the Source field to a range other than 0.0.0.0/0, or, B) ClickDeleteto remove the offending inbound rule 6. ClickSave rules
5.3Ensure no security groups allow ingress from ::/0 to remote server administration ports4
Attributes
- Profile
Level 1
- Section
5 Networking
- Description
Security groups provide stateful filtering of ingress and egress network traffic to AWS resources. It is recommended that no security group allows unrestricted ingress access to remote server administration ports, such as SSH to port
22and RDP to port3389.- Audit Procedure
Perform the following to determine if the account is configured as prescribed: 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. In the left pane, click
Security Groups3. For each security group, perform the following: 1. Select the security group 2. Click theInbound Rulestab 3. Ensure no rule exists that has a port range that includes port22,3389, or other remote server administration ports for your environment and has aSourceof::/0Note: A Port value ofALLor a port range such as0-1024are inclusive of port22,3389, and other remote server administration ports.- Impact Statement
When updating an existing environment, ensure that administrators have access to remote server administration ports through another mechanism before removing access by deleting the ::/0 inbound rule.
- Assessment Status
Automated
- Rationale Statement
Public access to remote server administration ports, such as 22 and 3389, increases resource attack surface and unnecessarily raises the risk of resource compromise.
- Remediation Procedure
Perform the following to implement the prescribed state: 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. In the left pane, click
Security Groups3. For each security group, perform the following: 1. Select the security group 2. Click theInbound Rulestab 3. Click theEdit inbound rulesbutton 4. Identify the rules to be edited or removed 5. Either A) update the Source field to a range other than ::/0, or, B) ClickDeleteto remove the offending inbound rule 6. ClickSave rules
5.4Ensure the default security group of every VPC restricts all traffic1
Attributes
- Profile
Level 2
- Section
5 Networking
- Description
A VPC comes with a default security group whose initial settings deny all inbound traffic, allow all outbound traffic, and allow all traffic between instances assigned to the security group. If you don't specify a security group when you launch an instance, the instance is automatically assigned to this default security group. Security groups provide stateful filtering of ingress/egress network traffic to AWS resources. It is recommended that the default security group restrict all traffic. The default VPC in every region should have its default security group updated to comply. Any newly created VPCs will automatically contain a default security group that will need remediation to comply with this recommendation. NOTE: When implementing this recommendation, VPC flow logging is invaluable in determining the least privilege port access required by systems to work properly because it can log all packet acceptances and rejections occurring under the current security groups. This dramatically reduces the primary barrier to least privilege engineering - discovering the minimum ports required by systems in the environment. Even if the VPC flow logging recommendation in this benchmark is not adopted as a permanent security measure, it should be used during any period of discovery and engineering for least privileged security groups.
- Audit Procedure
Perform the following to determine if the account is configured as prescribed: Security Group State 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. Repeat the next steps for all VPCs - including the default VPC in each AWS region: 3. In the left pane, click
Security Groups4. For each default security group, perform the following: 1. Select thedefaultsecurity group 2. Click theInbound Rulestab 3. Ensure no rule exist 4. Click theOutbound Rulestab 5. Ensure no rules exist Security Group Members 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. Repeat the next steps for all default groups in all VPCs - including the default VPC in each AWS region: 3. In the left pane, clickSecurity Groups4. Copy the id of the default security group. 5. Change to the EC2 Management Console at https://console.aws.amazon.com/ec2/v2/home 6. In the filter column type 'Security Group ID : < security group id from #4 >'- Impact Statement
Implementing this recommendation in an existing VPC containing operating resources requires extremely careful migration planning as the default security groups are likely to be enabling many ports that are unknown. Enabling VPC flow logging (of accepts) in an existing environment that is known to be breach free will reveal the current pattern of ports being used for each instance to communicate successfully.
- Assessment Status
Automated
- Rationale Statement
Configuring all VPC default security groups to restrict all traffic will encourage least privilege security group development and mindful placement of AWS resources into security groups which will in-turn reduce the exposure of those resources.
- Remediation Procedure
Security Group Members Perform the following to implement the prescribed state: 1. Identify AWS resources that exist within the default security group 2. Create a set of least privilege security groups for those resources 3. Place the resources in those security groups 4. Remove the resources noted in #1 from the default security group Security Group State 1. Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home 2. Repeat the next steps for all VPCs - including the default VPC in each AWS region: 3. In the left pane, click
Security Groups4. For each default security group, perform the following: 1. Select thedefaultsecurity group 2. Click theInbound Rulestab 3. Remove any inbound rules 4. Click theOutbound Rulestab 5. Remove any Outbound rules Recommended: IAM groups allow you to edit the "name" field. After remediating default groups rules for all VPCs in all regions, edit this field to add text similar to "DO NOT USE. DO NOT ADD RULES"
5.5Ensure routing tables for VPC peering are "least access"1
Attributes
- Profile
Level 2
- Section
5 Networking
- Description
Once a VPC peering connection is established, routing tables must be updated to establish any connections between the peered VPCs. These routes can be as specific as desired - even peering a VPC to only a single host on the other side of the connection.
- Audit Procedure
Review routing tables of peered VPCs for whether they route all subnets of each VPC and whether that is necessary to accomplish the intended purposes for peering the VPCs. From Command Line: 1. List all the route tables from a VPC and check if "GatewayId" is pointing to a <peering_connection_id> (e.g. pcx-1a2b3c4d) and if "DestinationCidrBlock" is as specific as desired.
aws ec2 describe-route-tables --filter "Name=vpc-id,Values=<vpc_id>" --query "RouteTables[*].{RouteTableId:RouteTableId, VpcId:VpcId, Routes:Routes, AssociatedSubnets:Associations[*].SubnetId}"- Assessment Status
Manual
- Rationale Statement
Being highly selective in peering routing tables is a very effective way of minimizing the impact of breach as resources outside of these routes are inaccessible to the peered VPC.
- Remediation Procedure
Remove and add route table entries to ensure that the least number of subnets or hosts as is required to accomplish the purpose for peering are routable. From Command Line: 1. For each <route_table_id> containing routes non compliant with your routing policy (which grants more than desired "least access"), delete the non compliant route:
aws ec2 delete-route --route-table-id <route_table_id> --destination-cidr-block <non_compliant_destination_CIDR>2. Create a new compliant route:aws ec2 create-route --route-table-id <route_table_id> --destination-cidr-block <compliant_destination_CIDR> --vpc-peering-connection-id <peering_connection_id>- Additional Information
If an organization has AWS transit gateway implemented in their VPC architecture they should look to apply the recommendation above for "least access" routing architecture at the AWS transit gateway level in combination with what must be implemented at the standard VPC route table. More specifically, to route traffic between two or more VPCs via a transit gateway VPCs must have an attachment to a transit gateway route table as well as a route, therefore to avoid routing traffic between VPCs an attachment to the transit gateway route table should only be added where there is an intention to route traffic between the VPCs. As transit gateways are able to host multiple route tables it is possible to group VPCs by attaching them to a common route table.
5.6Ensure that EC2 Metadata Service only allows IMDSv22
Attributes
- Profile
Level 1
- Section
5 Networking
- Description
When enabling the Metadata Service on AWS EC2 instances, users have the option of using either Instance Metadata Service Version 1 (IMDSv1; a request/response method) or Instance Metadata Service Version 2 (IMDSv2; a session-oriented method).
- Audit Procedure
From Console: 1. Sign in to the AWS Management Console and navigate to the EC2 dashboard at https://console.aws.amazon.com/ec2/. 2. In the left navigation panel, under the INSTANCES section, choose Instances. 3. Select the EC2 instance that you want to examine. 4. Check for the IMDSv2 status, and ensure that it is set to Required. From Command Line: 1. Run the describe-instances command using appropriate filtering to list the IDs of all the existing EC2 instances currently available in the selected region: aws ec2 describe-instances --region <region-name> --output table --query 'Reservations[].Instances[].InstanceId' 2. The command output should return a table with the requested instance IDs. 3. Now run the describe-instances command using an instance ID returned at the previous step and custom filtering to determine whether the selected instance has IMDSv2: aws ec2 describe-instances --region <region-name> --instance-ids <instance- id> --query 'Reservations[].Instances[].MetadataOptions' --output table 4. Ensure for all ec2 instances HttpTokens is set to required and State is set to applied. 5. Repeat steps no. 3 and 4 to verify other EC2 instances provisioned within the current region. 6. Repeat steps no. 1 – 5 to perform the audit process for other AWS regions.
- Assessment Status
Automated
- Rationale Statement
Instance metadata is data about your instance that you can use to configure or manage the running instance. Instance metadata is divided into categories, for example, host name, events, and security groups. When enabling the Metadata Service on AWS EC2 instances, users have the option of using either Instance Metadata Service Version 1 (IMDSv1; a request/response method) or Instance Metadata Service Version 2 (IMDSv2; a session-oriented method). With IMDSv2, every request is now protected by session authentication. A session begins and ends a series of requests that software running on an EC2 instance uses to access the locally-stored EC2 instance metadata and credentials. Allowing Version 1 of the service may open EC2 instances to Server-Side Request Forgery (SSRF) attacks, so Amazon recommends utilizing Version 2 for better instance security.
- Remediation Procedure
From Console: 1. Sign in to the AWS Management Console and navigate to the EC2 dashboard at https://console.aws.amazon.com/ec2/. 2. In the left navigation panel, under the INSTANCES section, choose Instances. 3. Select the EC2 instance that you want to examine. 4. Choose Actions > Instance Settings > Modify instance metadata options. 5. Ensure Instance metadata service is set to Enable and set IMDSv2 to Required. 6. Repeat steps no. 1 – 5 to perform the remediation process for other EC2 Instances in the all applicable AWS region(s). From Command Line: 1. Run the describe-instances command using appropriate filtering to list the IDs of all the existing EC2 instances currently available in the selected region: aws ec2 describe-instances --region <region-name> --output table -- query 'Reservations[].Instances[].InstanceId' 2. The command output should return a table with the requested instance IDs. 3. Now run the modify-instance-metadata-options command using an instance ID returned at the previous step to update the Instance Metadata Version: aws ec2 modify-instance-metadata-options --instance-id <instance-id> --http-tokens required --region <region-name> 4. Repeat steps no. 1 – 3 to perform the remediation process for other EC2 Instances in the same AWS region. 5. Change the region by updating --region and repeat the entire process for other regions.