CVE-2026-6736 Auth bypass in Enterprise Server
Unauthenticated attackers can create local user accounts bypassing external identity providers on GitHub Enterprise Server instances configured with external authentication.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-6736?
CVE-2026-6736 is a medium-severity authentication bypass vulnerability in Github Enterprise Server, published on 7 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-306
Which versions are affected by CVE-2026-6736?
It affects 1 product.
Products include Github Enterprise Server.
How do I fix CVE-2026-6736?
No fix has been published for CVE-2026-6736 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-6736 being exploited?
There is no known exploitation of CVE-2026-6736 in the wild and no public exploit code.
Other vulnerabilities in Github Enterprise Server
- CVE-2024-4985 Auth bypass in Enterprise Server
- CVE-2022-23739 Missing authorization in GitHub Enterprise Server
- CVE-2022-46255 Improper Limitation of a Pathname to a Restricted Directory in GitHub Enterprise Server leading to RCE
- CVE-2021-22869 Improper access control in GitHub Enterprise Server allows self-hosted runners to execute outside their control group
- CVE-2024-9487 Auth bypass in Enterprise Server
Sources
Also known as GHSA-2gcr-p5w4-5hh8.