Bitbucket Audit: Unauthorized Access to a Resource

Flags Bitbucket audit events reporting unauthorized access attempts to a resource.

FreeReviewedSigma · Critical · v5
Product
bitbucket
Service
audit
Author
Muhammad Faisal (@faisalusuf) (SigmaHQ), DRL 1.1
Published
2024-02-25
Updated
2026-07-31
title: "Bitbucket Audit: Unauthorized Access to a Resource"
id: 35e5f099-bb50-4556-8bc4-45ddf0bbbaf2
status: test
description: This rule flags Bitbucket audit events where an action is recorded as an unauthorized access attempt to a resource. Attackers may probe for restricted content or operations, and these events indicate access attempts that were not permitted. The detection relies on Bitbucket audit log records matching the event category and action for unauthorized access to a resource.
references:
  - https://confluence.atlassian.com/bitbucketserver/audit-log-events-776640423.html
  - https://github.com/SigmaHQ/sigma/blob/master/rules/application/bitbucket/audit/bitbucket_audit_unauthorized_access_detected.yml
author: Muhammad Faisal (@faisalusuf), Huntrule Team
date: 2024-02-25
tags:
  - attack.resource-development
  - attack.t1586
logsource:
  product: bitbucket
  service: audit
  definition: 'Requirements: "Advance" log level is required to receive these audit events.'
detection:
  selection:
    auditType.category: Security
    auditType.action: Unauthorized access to a resource
  condition: selection
falsepositives:
  - Access attempts to non-existent repositories or due to outdated plugins. Usually "Anonymous" user is reported in the "author.name" field in most cases.
level: critical
license: DRL-1.1
related:
  - id: 7215374a-de4f-4b33-8ba5-70804c9251d3
    type: derived