GitLab has remediated an issue in GitLab CE/EE affecting all versions from 16.11 before 18.7.6, 18.8 before 18.8.6, and 18.9 before 18.9.2 that could have allowed an unauthenticated user to cause a denial of service condition due to improper input validation when processing specially crafted JSON payloads in the protected branches API.
https://about.gitlab.com/releases/2026/03/11/patch-release-gitlab-18-9-2-released/