Description
An issue has been discovered in GitLab CE/EE affecting all versions starting from 8.14 before 16.0.8, all versions starting from 16.1 before 16.1.3, all versions starting from 16.2 before 16.2.2. A Regular Expression Denial of Service was possible via sending crafted payloads which use AutolinkFilter to the preview_markdown endpoint.
References
https://gitlab.com/gitlab-org/gitlab/-/issues/415995
https://hackerone.com/reports/1959727