Vulnerability · Published Oct 14, 2026 · Assigned by Gitea

CVE-2026-66877Gitea fork workflow approval bypass through concurrency cancellation

High 8.1

In plain English

A high-severity improper access control in Gitea from Gitea. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities).

Severity (CVSS 3.1)8.1High

Exploit odds (30 days)0.4%top 62.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
Gitea	Gitea	0 – through 1.27.2

Weakness: CWE-284 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

References

GitHub Security Advisory GHSA-v2w8-m4gr-qj65 vendor-advisory
Gitea 1.27.3 release announcement release-notes
Fix: go-gitea/gitea pull request #39005 patch
Fix: go-gitea/gitea pull request #39018 patch
go-gitea/gitea v1.27.3 release release-notes