GitLab has remediated an issue in GitLab CE/EE affecting all versions from 10.6 before 18.9.6, 18.10 before 18.10.4, and 18.11 before 18.11.1 that could have allowed an authenticated user to cause denial of service under certain conditions by exhausting server resources by making crafted requests to a discussions endpoint.
https://hackerone.com/reports/2915694
https://gitlab.com/gitlab-org/gitlab/-/work_items/511312
https://about.gitlab.com/releases/2026/04/22/patch-release-gitlab-18-11-1-released/