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Indicator Removal: Delete IAM Entities
AWS Specific Sub-Technique
Other sub-techniques of Indicator Removal (2)
| ID | Name |
|---|---|
| T1070.A001 | Delete IAM Entities |
A prerequisite for this technique is that a threat actor has already gained control of an AWS identity with the permissions to perform the actions in the AWS CloudTrail Event Name(s) section.
With access to an AWS identity that has the appropriate permissions, threat actors may create users and roles within an AWS account, then, these users or roles can be deleted after unauthorized actions have been taken with the users or roles in an attempt to remove indicators of compromise, misguide an incident responder, and slow down an investigation.
This technique uses the same event names as the Account Access Removal technique (iam:DeleteUser), however, the difference is that in the Account Access Removal technique, the roles and users that are deleted are legitimate and are created by an administrator for the AWS account. With this technique, a threat actor first creates the users and roles, performs unauthorized actions with the users and roles, and then deletes the previously created users and roles to remove their existence.
Detection
AWS Specific Content
When this technique is used by the threat actor, actions taken by the threat actor using the credentials obtained will be logged in CloudTrail. You can use the Event history page in the AWS CloudTrail console to view the last 90 days of management events in an AWS Region for the events listed in the AWS CloudTrail Event Name(s) section, such as
iam:DeleteUser.A separate CloudTrail trail will give you an ongoing record of events in your AWS account past 90 days and can be configured to log events in multiple regions. You can also review events using the console as well as the AWS CLI.
It is also possible to create a CloudWatch metric filter to watch for when specific AWS API calls are used and perform notification actions if logged, and additionally configure CloudWatch to automatically perform an action in response to an alarm.
Mitigation
AWS Specific Content
You can make sure that principals are scoped with the least-privileged permissions necessary to perform duties, limiting the ability to perform unauthorized actions in an AWS account when not required. One possible method of applying the principle of least-privileged permissions is to use Service Control Policies to restrict the maximum available permissions for the IAM users and IAM roles within your AWS Organizations accounts (note - you should test SCPs in a development environment before deploying them in production).
You can also use IAM Access Analyzer to regularly review and verify access and manage permissions across your AWS environment, which will highlight AWS identities with excessive permissions and the actions performed by those identities.