Security Advisory
CVE-2026-86197
CVE vulnerability detail - eXtreme Datacenter Security Operations
Description
Grav before 2.0.20 contains a cross-site scripting vulnerability in the Twig sandbox policy that allowlists addJs and addCss methods on Grav\Common\Assets without proper output escaping. Page editors can inject arbitrary script by registering malicious assets or injecting attributes, which are rendered unescaped into document head tags and executed for all visitors including administrators.