Reliance on Untrusted Inputs in a Security Decision in Gitea - CVE-2026-66874
Published: August 31, 2026
Vulnerability identifier: #VU146351
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-66874
CWE-ID: CWE-807
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to bypass required status checks and merge unverified code into a protected branch.
The vulnerability exists due to reliance on untrusted inputs in a security decision in the Actions workflow status check handling for pull requests when processing a fork pull request with a workflow definition from the pull request head that is excluded by its own filters. A remote user can define a workflow whose name matches a required status check context and configure a filter that never matches to bypass required status checks and merge unverified code into a protected branch.
No workflow run is created, so the fork approval gate does not apply.
Affected software
Gitea
How to mitigate CVE-2026-66874
Install security update from vendor's website.
Gitea - update to 1.27.3