High 8.1Published Oct 14, 2026

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

Updated under an hour ago (2026-10-19 05:50 UTC)

Does this affect you?

It affects Gitea. Add what you run to find out whether that includes you.

EPSS puts the chance of exploitation in the next 30 days at 0.43%, higher than 35% of scored CVEs.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for Gitea

Exploited in the last 30 days

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.

CVSS: 8.1 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Weakness (CWE): CWE-284
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): 0.43% (percentile 35)
Assigned by: Gitea
NVD analysis: Deferred
Record last updated: Oct 15, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Gitea Gitea gitea:gitea (from the name)	through 1.27.2	CNA record

References

https://github.com/go-gitea/gitea/security/advisories/GHSA-v2w8-m4gr-qj65vendor-advisory
https://blog.gitea.com/release-of-1.27.3/release-notes
https://github.com/go-gitea/gitea/pull/39005patch
https://github.com/go-gitea/gitea/pull/39018patch
https://github.com/go-gitea/gitea/releases/tag/v1.27.3release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.