CVE-2026-5845 (GCVE-0-2026-5845)
Vulnerability from cvelistv5
Published
2026-04-21 22:42
Modified
2026-04-22 18:04
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-639 - Authorization bypass through User-Controlled key
Summary
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.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| GitHub | Enterprise Server |
Version: 3.20.0 ≤ Version: 3.19.0 ≤ 3.19.4 Version: 3.18.0 ≤ 3.18.7 Version: 3.17.0 ≤ 3.17.13 Version: 3.16.0 ≤ 3.16.16 Version: 3.15.0 ≤ 3.15.20 Version: 3.14.0 ≤ 3.14.25 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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