GitLab has remediated an issue in GitLab CE/EE affecting all versions from 13.12 to 18.2.8, 18.3 to 18.3.4, and 18.4 to 18.4.2 that could make the GitLab instance unresponsive or severely degraded by sending crafted GraphQL queries requesting large repository blobs.
https://about.gitlab.com/releases/2025/10/08/patch-release-gitlab-18-4-2-released/