CVE-2026-5845
Description
An improper authorization vulnerability in scoped user-to-server (ghu_) token authorization in GitHub Enterprise Server allows an authenticated attacker to access private repositories outside the intended installation scope, which can include write operations, via an authorization fallback that treated a revoked/deleted installation as a global installation context, which could be chained with token revocation timing and SSH push attribution to obtain and reuse a victim-scoped token. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.20.1, 3.19.5, 3.18.8, 3.17.14, 3.16.17, 3.15.21, and 3.14.26. This vulnerability was reported via the GitHub Bug Bounty program.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| github | enterprise_server | {"endExcluding":"3.14.26"} | 3.14.26 |
| github | enterprise_server | 3.20.0 | |
References
- https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.26
- https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.21
- https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.17
- https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.14
- https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.8
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.5
- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.1
CWEs
CWE-639
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.