CVE-2026-66877

Gitea fork workflow approval bypass through concurrency cancellation

Published Oct 14, 2026 CVSS 3.1 · 8.1 High EPSS < 1% KEV · Not listed
Description
Gitea enforces first-time fork contributor approval by blocking jobs, but some job transition and dispatch paths do not re-check the run's approval requirement. A separate run sharing a job-level concurrency group can cancel a pending job and cause its blocked sibling jobs to be re-emitted and dispatched without approval. This allows unreviewed workflow code to execute on self-hosted runners; fork secrets remain withheld and the run token remains read-only.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Gitea
Gitea gitea
Vendors & Products Gitea
Gitea gitea
Type Values Removed Values Added
Weaknesses CWE-284
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Gitea enforces first-time fork contributor approval by blocking jobs, but some job transition and dispatch paths do not re-check the run's approval requirement. A separate run sharing a job-level concurrency group can cancel a pending job and cause its blocked sibling jobs to be re-emitted and dispatched without approval. This allows unreviewed workflow code to execute on self-hosted runners; fork secrets remain withheld and the run token remains read-only.
Title Gitea fork workflow approval bypass through concurrency cancellation
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Gitea
Published
Updated
Oct 15, 2026, 3:56 AM
Reserved
Aug 13, 2026, 4:50 PM
Status
Deferred
Published
Oct 14, 2026, 3:17 PM
Modified
Oct 15, 2026, 4:18 AM