GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.9 before 18.9.2 that could have allowed an unauthenticated user to cause a denial of service by sending specially crafted GraphQL requests due to uncontrolled recursion under certain circumstances.
https://about.gitlab.com/releases/2026/03/11/patch-release-gitlab-18-9-2-released/