GitLab CVSS 10.0 Integer Overflow issue

GitLab released critical patch versions (19.5.1, 19.4.3, and others) on October 21, 2026 to address multiple security vulnerabilities, including a critical CVSS 10.0 integer overflow issue in the regular expression compiler. All self-managed GitLab installations are strongly urged to upgrade immediately, while GitLab.com and Dedicated tenants are already protected with the patched versions. The security fixes address a range of issues from critical to low severity, including authentication, access control, and cache poisoning vulnerabilities.