CVE-2026-1388: GitLab

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 9.2 before 18.7.5, 18.8 before 18.8.5, and 18.9 before 18.9.1 that could have allowed an unauthenticated user to cause regular expression denial of service by sending specially crafted input to a merge request endpoint under certain conditions.

Affected products

• GitLab GitLab: from 9.2.0, before 18.7.5 (fixed in 18.7.5); from 18.8.0, before 18.8.5 (fixed in 18.8.5); version 18.9.0 only

Published 2026-02-25. Last modified 2026-06-17.