CVE-2026-3307

What it is

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.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. Limited direct impact.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-04-21 23:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-26 22:10 UTC Last updatedMost recent change to the record

Details

Published

2026-04-21 23:16 UTC

Last modified

2026-10-26 22:10 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-639 · Insecure direct object reference

Record status

Analyzed

Affected

• GitHub Enterprise Server < 3.14.26
• GitHub Enterprise Server < 3.15.21
• GitHub Enterprise Server < 3.16.17
• GitHub Enterprise Server < 3.17.14
• GitHub Enterprise Server < 3.18.8
• GitHub Enterprise Server < 3.19.5
• GitHub Enterprise Server 3.20.0

Attack profile CVSS 4.0 · 5.3

Attack vector

Network

Complexity

Low

Attack requirements

None

Privileges needed

Low

User interaction

None

Confidentiality

None

Integrity

Low

Availability

None