Vulnerability in GitHub Enterprise Server

[ Description ]Official description

A remote code execution vulnerability was identified in GitHub Enterprise Server in the Git service (babeld). babeld held references into internal collections while calling into the SSH library, where a re-entrant callback could modify a collection and invalidate those references. An attacker with an account and SSH access to the instance could leverage this use-after-free into a controlled write and run arbitrary commands as babeld, including disclosure of its environment secrets. Exploitation required per-build memory offsets; failed attempts crashed babeld. This affected all releases prior to 3.23 and was fixed in 3.22.3, 3.21.8, 3.20.10, and 3.19.14. This vulnerability was reported via the GitHub Bug Bounty program.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund3 Nov 2026WID-SEC-2026-4334

  Microsoft GitHub Enterprise Server: Multiple vulnerabilities Translated from German

  Risk highCVE-2026-118237CVE-2026-110288CVE-2026-104608

[ References ]References

• docs.github.com/en/enterprise-server@3.19/admin/release-notes
• docs.github.com/en/enterprise-server@3.20/admin/release-notes
• docs.github.com/en/enterprise-server@3.21/admin/release-notes
• docs.github.com/en/enterprise-server@3.22/admin/release-notes