Auth bypass in Github Enterprise Server
CVE-2026-3306
An improper authorization vulnerability was identified in GitHub Enterprise Server that allowed a user with read access to a repository and write access to a project to modify issue and pull request metadata through the project. When adding an item to a project that already existed, column value updates were applied without verifying the actor's repository write permissions. This vulnerability was reported via the GitHub Bug Bounty program and has been fixed in GitHub Enterprise Server versions 3.14.24, 3.15.19, 3.16.15, 3.17.12, 3.18.6 and 3.19.3.
Vulnerability class: IDOR (Insecure Direct Object Reference)
EPSS: 0.003 (24.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.
Affected products
- Github Enterprise Server — versions 3.14.0, 3.15.0, 3.16.0
- Github Enterprise_server
Weakness classification (CWE)
Public proof-of-concept exploits
References
- product-cna@github.com (Release Notes)
- product-cna@github.com (Release Notes)
- product-cna@github.com (Release Notes)
- product-cna@github.com (Release Notes)
- product-cna@github.com (Release Notes)
- product-cna@github.com (Release Notes)
Frequently asked questions
- What is CVE-2026-3306?
- CVE-2026-3306 is a medium-severity vulnerability in Github Enterprise Server, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-03-10.
- How severe is CVE-2026-3306?
- Medium severity. CVSS v3 base score is 4.3 out of 10.
- Is CVE-2026-3306 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.