huntrule

AWS Bedrock Guardrail Deletion via CloudTrail DeleteGuardrail API

Alerts on CloudTrail DeleteGuardrail events indicating an AWS Bedrock guardrail was removed.

FreeReviewedSigma · Medium · v5
Product
aws
Service
cloudtrail
Author
Marco Pedrinazzi (@pedrinazziM) (InTheCyber) (SigmaHQ), DRL 1.1
Published
2026-07-10
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule flags CloudTrail events where the Bedrock service reports a DeleteGuardrail API call. Deleting a guardrail can reduce or remove model safety controls, which may enable unsafe or unauthorized responses. It relies on AWS CloudTrail telemetry for eventName DeleteGuardrail with eventSource bedrock.amazonaws.com.

Reporting behind it

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Malicious FIN7 AvNeutralizer EDR Killer Execution via Masqueraded Binary (via process_creation)
Suspicious Process Explorer Kernel Driver Dropped as PED.sys via File Creation (via file_event)
AWS Bedrock Guardrail Deletion via CloudTrail DeleteGuardrail API
Pivot detection · T1685 · 9 related

Changelog

v5
  1. v5
    Candidate ingested via manual entry.2026-07-31
  2. v4
    Candidate ingested via manual entry.2026-07-31
  3. v3
    Candidate ingested via manual entry.2026-07-31
  4. v2
    Candidate ingested via manual entry.2026-07-31
  5. v1
    No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.