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Data Destruction: RDS Instances and Backups
AWS Specific Sub-Technique
Other sub-techniques of Data Destruction (4)
| ID | Name |
|---|---|
| T1485.001 | Lifecycle-Triggered Deletion |
| T1485.A001 | RDS Instances and Backups |
| T1485.A003 | S3 Object and Bucket Deletion |
AWS Specific Content
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 delete Amazon RDS backups within an AWS account to block victims from recovering their data in the event of an RDS instance or cluster deletion, and then delete the RDS instance for high impact in a victim's AWS account, typically as part of a ransomware campaign. The
rds:ModifyDBCluster API is used by the threat actor to turn off deletion protection for a cluster, and the rds:ModifyDBInstance API is also used to turn off deletion protection and additionally set the backup retention period to 0, effectively removing automated snapshots.This technique is related to Cloud Database Discovery > Query RDS, as a threat actor will typically view information about RDS instances and snapshots in the AWS account (
s3:DescribeDBInstances and s3:DescribeDBSnapshots) prior to deleting the RDS instances and snapshots.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
rds:DeleteDBInstance.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.
Additional information on how to protect data in RDS is available here. Replication can also help in some instances, and can be configured using the steps in this guide.
This technique is typically used by threat actors as part of a ransomware campaign. AWS has published several resources on how to protect against ransomware and mitigate some of the actions described by this technique. However, an effective mitigation against data destruction is through the implementation and testing of robust backup processes.