GitLab fixes prompt injection vulnerability CVE-2026-96893 in Duo Agent Platform

On October 12, 2026, GitLab released patch versions 19.4.2, 19.3.5, and 19.2.8, fixing the prompt injection vulnerability CVE-2026-96893 in the GitLab Duo Agent Platform and other security issues. This vulnerability has a CVSS score of 7.3; authenticated users can inject specially crafted content into AI agent instructions, potentially leading to unintended commands being executed on behalf of other users. Affected versions are GitLab EE from 19.1 up to but not including 19.2.8, from 19.3 up to but not including 19.3.5, and from 19.4 up to but not including 19.4.2. It was discovered internally by GitLab team member Mert Coskuner. The same batch of patches also fixed an integer overflow vulnerability in the CI/CD regex compiler, CVE-2026-97229 (CVSS 10.0), and a governance control bypass vulnerability in the Duo Agent Platform, CVE-2026-105458 (CVSS 4.3).