Vulnerability · Published Nov 3, 2026 · Assigned by GitHub_P
CVE-2026-104608Use-after-free vulnerability in GitHub Enterprise Server allowed remote code execution in the Git service
High 7.7
In plain English
A high-severity use-after-free in Enterprise Server from GitHub. 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 34% of all known vulnerabilities).
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| GitHub | Enterprise Server | 3.19.0 – before 3.19.*3.20.0 – before 3.20.*3.21.0 – before 3.21.*3.22.0 – before 3.22.* |
Weakness: CWE-416, CWE-1265 · Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:L/SI:N/SA:N
References
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.14 release-notes
- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.10 release-notes
- https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.8 release-notes
- https://docs.github.com/en/enterprise-server@3.22/admin/release-notes#3.22.3 release-notes