Vulnerability · Published Apr 21, 2026 · Assigned by GitHub_P
CVE-2026-3307Authorization bypass in GitHub Enterprise Server secret scanning push protection allows cross-repository modification of delegated bypass reviewers
Medium 5.3
In plain English
A medium-severity authorization bypass via user-controlled key in Enterprise Server from GitHub. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities).
Official description
An authorization bypass vulnerability was identified in GitHub Enterprise Server that allowed an attacker with admin access on one repository to modify the secret scanning push protection delegated bypass reviewer list on another repository by manipulating the owner_id parameter in the request body. Authorization was verified against the repository in the URL, but the action was applied to a different repository specified in the request body. The impact is limited to assigning existing trusted users as bypass reviewers; it does not allow adding arbitrary external users. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7, 3.19.4 and 3.20.1. This vulnerability was reported via the GitHub Bug Bounty program.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| GitHub | Enterprise Server | 3.14.0 – through 3.14.243.15.0 – through 3.15.193.16.0 – through 3.16.153.17.0 – through 3.17.123.18.0 – through 3.18.63.19.0 – through 3.19.33.20 – through 3.20.0 |
Weakness: CWE-639 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
References
- https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.25
- https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.20
- https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.16
- https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.13
- https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.7
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.4
- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.1