CVE-2025-66299: Grav is Vulnerable to Security Sandbox Bypass with SSTI (Server Side Template Injection)

December 2, 2025

Grav CMS is vulnerable to a Server-Side Template Injection (SSTI) that allows any authenticated user with editor permissions to execute arbitrary code on the remote server, bypassing the existing security sandbox.

References

github.com/advisories/GHSA-gjc5-8cfh-653x
github.com/getgrav/grav
github.com/getgrav/grav/commit/e37259527d9c1deb6200f8967197a9fa587c6458
github.com/getgrav/grav/security/advisories/GHSA-gjc5-8cfh-653x
nvd.nist.gov/vuln/detail/CVE-2025-66299

Code Behaviors & Features

Detect and mitigate CVE-2025-66299 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →