GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.10 before 18.11.6, 19.0 before 19.0.3, and 19.1 before 19.1.1 that under certain conditions could have allowed an unauthenticated user to execute arbitrary JavaScript in a user's browser session due to improper path validation under certain conditions.
Upgrade to versions 18.11.6, 19.0.3, 19.1.1 or above.