GitLab CE/EE Denial-of-Service Vulnerability via Malicious Webhook Endpoints

A denial-of-service vulnerability has been identified in GitLab Community Edition (CE) and Enterprise Edition (EE) versions 5.2 prior to 18.2.8, 18.3 prior to 18.3.4, and 18.4 prior to 18.4.2. This vulnerability could have allowed an authenticated attacker to create a denial-of-service condition by configuring malicious webhook endpoints that sent crafted HTTP responses, impacting the responsiveness of the GitLab instance.

Impact

Exploitation of this vulnerability could lead to a degraded or unresponsive GitLab instance.

Remediation

Users are advised to upgrade to GitLab versions 18.4.2, 18.3.4, or 18.2.8. Instructions for updating GitLab can be found on the GitLab Update page.