Cross-site scripting in Grav CMS - CVE-2025-66310
Published: May 5, 2026
Vulnerability identifier: #VU130062
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear
CVE-ID: CVE-2025-66310
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Grav CMS
Affected software:
Grav CMS
Grav CMS
Detailed vulnerability description
The vulnerability allows a remote user to execute arbitrary script in a user's browser.
The vulnerability exists due to cross-site scripting in the /admin/pages/[page] endpoint parameter data[header][template] when handling crafted page update requests. A remote privileged user can submit a specially crafted value in the template field to execute arbitrary script in a user's browser.
User interaction is required for the affected content to be rendered, including in the administrative interface or frontend view.
How to mitigate CVE-2025-66310
Install security update from vendor's website.