CVE-2026-15783: Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed reading private repository metadata via delegated bypass rule suites
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.
CWE-862
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
GitHub: Enterprise Server
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- docs.github.com/en/enterprise-server@3.17/admin/release-notes (opens in new tab)
- docs.github.com/en/enterprise-server@3.18/admin/release-notes (opens in new tab)
- docs.github.com/en/enterprise-server@3.19/admin/release-notes (opens in new tab)
- docs.github.com/en/enterprise-server@3.20/admin/release-notes (opens in new tab)
- docs.github.com/en/enterprise-server@3.21/admin/release-notes (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)