CVE-2026-42845

The form plugin for Grav adds the ability to create and use forms. Prior to 9.1.0 , there is an unauthenticated page-content overwrite via file upload (GHSA-w4rc-p66m-x6qq). Public form uploads now strip path components from the POST-supplied filename and hard-block page-content extensions (`md`, `yaml`, `yml`, `json`, `twig`, `ini`) regardless of the configurable dangerous-extensions list. A permissive `accept` policy combined with the default `destination: self@` could otherwise let an attacker overwrite the page's own `.md` and pivot to super-admin via a `process: save` action. This vulnerability is fixed in 9.1.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/getgrav/grav-plugin-form/commit/48bacc4187e1cff815000e526d5ca2878484867f
https://github.com/getgrav/grav/security/advisories/GHSA-w4rc-p66m-x6qq
https://github.com/getgrav/grav/security/advisories/GHSA-w4rc-p66m-x6qq

Configurations

No configuration.

History

12 May 2026, 14:17

Type	Values Removed	Values Added
References	~~() https://github.com/getgrav/grav/security/advisories/GHSA-w4rc-p66m-x6qq -~~	() https://github.com/getgrav/grav/security/advisories/GHSA-w4rc-p66m-x6qq -

11 May 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-11 17:16

Updated : 2026-05-12 14:51

NVD link : CVE-2026-42845

Mitre link : CVE-2026-42845

CVE.ORG link : CVE-2026-42845

JSON object : View

Products Affected

No product.

CWE

CWE-73

External Control of File Name or Path

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