CVE-2026-5173: GitLab

High severity, CVSS 8.5. EPSS: 0.4% chance of exploitation in the next 30 days.

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 16.9.6 before 18.8.9, 18.9 before 18.9.5, and 18.10 before 18.10.3 that could have allowed an authenticated user to invoke unintended server-side methods through websocket connections due to improper access control.

Affected products

• GitLab GitLab: from 16.9.6, before 18.8.9 (fixed in 18.8.9); from 18.9.0, before 18.9.5 (fixed in 18.9.5); from 18.10.0, before 18.10.3 (fixed in 18.10.3)

Published 2026-04-08. Last modified 2026-07-24.