CVE-2023-3909: GitLab

Medium severity, CVSS 6.5. EPSS: 0.6% chance of exploitation in the next 30 days.

An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.3 before 16.3.6, all versions starting from 16.4 before 16.4.2, all versions starting from 16.5 before 16.5.1. A Regular Expression Denial of Service was possible by adding a large string in timeout input in gitlab-ci.yml file.

Affected products

• GitLab GitLab: from 12.3.0, before 16.3.6 (fixed in 16.3.6); from 16.4.0, before 16.4.2 (fixed in 16.4.2); version 16.5.0 only

Published 2023-11-06. Last modified 2026-06-17.