CVE-2023-6840: Missing Authorization in GitLab

Severity: medium (CVSS 6.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-02-07 · updated 2026-06-17
Weakness: CWE-862

Description

An issue has been discovered in GitLab EE affecting all versions from 16.4 prior to 16.6.7, 16.7 prior to 16.7.5, and 16.8 prior to 16.8.2 which allows a maintainer to change the name of a protected branch that bypasses the security policy added to block MR.

Affected products

GitLab: from 16.4.0 before 16.6.7; from 16.7.0 before 16.7.5; from 16.8.0 before 16.8.2 — fixed in 16.6.7, 16.7.5, 16.8.2

How to fix

Upgrade to a fixed version: GitLab 16.6.7, 16.7.5, 16.8.2. Check the vendor advisory for mitigations.

References

https://gitlab.com/gitlab-org/gitlab/-/issues/435500
https://hackerone.com/reports/2280292
https://gitlab.com/gitlab-org/gitlab/-/issues/435500
https://hackerone.com/reports/2280292

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