GitLab has remediated an issue in GitLab CE/EE affecting all versions from 12.4 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 by overwhelming system resources under certain conditions due to insufficient resource allocation limits in the GraphQL API.
https://hackerone.com/reports/3098035
https://gitlab.com/gitlab-org/gitlab/-/work_items/537422
https://about.gitlab.com/releases/2026/04/22/patch-release-gitlab-18-11-1-released/