This detection rule identifies instances where the default encryption for Amazon Elastic Block Store (EBS) has been disabled in the current AWS region. Disabling the default encryption can leave sensitive data unprotected, making it vulnerable to unauthorized access. This rule monitors CloudTrail logs for the specific action 'DisableEbsEncryptionByDefault' and alerts security teams if such a change is detected. To ensure comprehensive security, it is crucial to investigate the user or role responsible for this action, assess their permissions, review the event outcomes, and analyze the overall AWS security posture. The rule outlines investigation and response steps, advising immediate action if unauthorized modifications are suspected.