CVE-2026-15783 Missing authorization in Enterprise Server
Authenticated users with write access can read private repository metadata from unauthorized repositories due to missing authorization checks.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-15783?
CVE-2026-15783 is a medium-severity missing authorization vulnerability in GitHub Enterprise Server, published on 17 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user with write access to any repository to read metadata from private repositories they did not have access to, including private repository owners and names, branch names, commit SHAs, commit messages, and the pushing actor. The delegated bypass endpoint resolved a rule suite directly from an attacker-supplied, encoded identifier without verifying that the requesting user could read the rule suite's repository, and because these identifiers are sequential an attacker could enumerate them across the instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.18, 3.18.12, 3.19.9, 3.20.5, and 3.21.3. This vulnerability was reported via the GitHub Bug Bounty program.
Weakness: CWE-862
Which versions are affected by CVE-2026-15783?
How do I fix CVE-2026-15783?
No fix has been published for CVE-2026-15783 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-15783 being exploited?
There is no known exploitation of CVE-2026-15783 in the wild and no public exploit code.
Sources
Also known as GHSA-qhvh-xjh2-7c8c.