CVE-2026-6736 (GCVE-0-2026-6736)
Vulnerability from cvelistv5
Published
2026-05-07 21:14
Modified
2026-05-08 13:57
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-306 - Missing Authentication for Critical Function
Summary
An authentication bypass vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to create a local user account, bypassing the configured external identity provider. When external authentication was enabled, the signup endpoint did not properly enforce the authentication restriction, allowing account creation and session establishment without identity provider validation. The created account was limited to the default base permissions configured on the instance. Exploitation required network access to a GHES instance configured with an external authentication provider. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.20.2, 3.19.6, 3.18.9, 3.17.15, and 3.16.18.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| GitHub | Enterprise Server |
Version: 3.16.0 ≤ 3.16.17 Version: 3.17.0 ≤ 3.17.14 Version: 3.18.0 ≤ 3.18.8 Version: 3.19.0 ≤ 3.19.5 Version: 3.20.0 ≤ 3.20.1 |
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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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