Arbitrary file upload in Form plugin for Grav CMS - CVE-2024-27923

 

Arbitrary file upload in Form plugin for Grav CMS - CVE-2024-27923

Published: March 4, 2024 / Updated: May 20, 2026


Vulnerability identifier: #VU130048
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2024-27923
CWE-ID: CWE-434
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote user to execute arbitrary code.

The vulnerability exists due to improper access control and unrestricted upload of file with dangerous type in the frontmatter form handling feature when creating a page and submitting a crafted contact form. A remote user can add the data[_json][header][form] parameter to enable frontmatter, create a form that saves a .phar file, and submit PHP code to execute arbitrary code.

Exploitation requires an account capable of creating pages.


Affected software

Form plugin for Grav CMS

How to mitigate CVE-2024-27923

Install security update from vendor's website.

Form plugin for Grav CMS - update to 7.2.2

External References

Related Security Bulletins