Identifies attempts to suppress or blind Amazon GuardDuty without deleting the detector outright. Adversaries with GuardDuty permissions can create or update a trusted IP set (CreateIPSet/UpdateIPSet) so that traffic from listed addresses is never flagged, tamper with the threat intelligence feed used to generate findings (CreateThreatIntelSet/UpdateThreatIntelSet), or soft-disable the detector via UpdateDetector with Enable set to false. All three techniques leave the detector itself intact, evading detections that only look for detector deletion.

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Detects attempts to disassociate or manipulate Amazon GuardDuty member accounts within an AWS organization. In multi-account GuardDuty deployments, a delegated administrator account aggregates findings from member accounts. Adversaries may attempt to disassociate member accounts, delete member relationships, stop monitoring members, or delete pending invitations to break this centralized visibility. These actions can be precursors to or alternatives for deleting GuardDuty detectors entirely, allowing attackers to operate undetected in member accounts while the administrator account loses visibility. This rule identifies successful API calls that manipulate GuardDuty member relationships, which are rare in normal operations and warrant immediate investigation.

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