GitLab CE/EE HTML Injection Vulnerability in Merge Request Titles

A vulnerability allowing HTML injection in merge request titles has been identified in GitLab Community Edition (CE) and Enterprise Edition (EE). This issue affects all versions from 15.6 prior to 18.4.6, 18.5 prior to 18.5.4, and 18.6 prior to 18.6.2. The vulnerability could have allowed an authenticated user to leak sensitive information by crafting specific merge request titles.

Impact

Exploitation of this vulnerability could lead to unauthorized information disclosure by allowing sensitive data to be extracted from manipulated merge request titles.

Remediation

Users are advised to upgrade to GitLab versions 18.6.2, 18.5.4, or 18.4.6. Instructions for updating GitLab can be found on the GitLab Update page. For GitLab Runner, refer to the Updating the Runner page.