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
title: AWS Bedrock Guardrail Deletion via CloudTrail DeleteGuardrail API
id: 5bcde200-5145-4008-9c58-e3a489daf4c6
status: experimental
description: 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.
references:
  - https://docs.aws.amazon.com/bedrock/latest/APIReference/API_DeleteGuardrail.html
  - https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/aws/cloudtrail/aws_cloudtrail_bedrock_guardrail_deleted.yml
author: Marco Pedrinazzi (@pedrinazziM) (InTheCyber), Huntrule Team
date: 2026-07-10
tags:
  - attack.defense-impairment
  - attack.t1685
logsource:
  product: aws
  service: cloudtrail
detection:
  selection:
    eventName: DeleteGuardrail
    eventSource: bedrock.amazonaws.com
  condition: selection
falsepositives:
  - Legitimate guardrail deletion by authorized identities.
level: medium
license: DRL-1.1
related:
  - id: 59b70e4d-dd17-44a9-b740-acf07ae3eb6a
    type: derived