CVE-2026-42841

Grav is a file-based Web platform. Prior to 2.0.0-beta.2, an authenticated user with page editing permissions can inject an executable JavaScript event-handler attribute into rendered image HTML through Grav's Markdown media action syntax. The issue is caused by Markdown image query parameters being converted into callable media actions. The public attribute() media method can be reached this way, allowing an editor to set an arbitrary HTML attribute name and value on the generated image element. This vulnerability is fixed in 2.0.0-beta.2.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.7 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/getgrav/grav/commit/5a12f9be8314682c8713e569e330f11805d0a663	Patch
https://github.com/getgrav/grav/security/advisories/GHSA-r7fx-8g49-7hhr	Exploit Patch Vendor Advisory
https://github.com/getgrav/grav/security/advisories/GHSA-r7fx-8g49-7hhr	Exploit Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:getgrav:grav::::::::
	cpe:2.3:a:getgrav:grav:2.0.0:beta1::::::

History

26 Oct 2026, 18:10

Type	Values Removed	Values Added
Summary		(es) Grav es una plataforma web basada en archivos. Antes de 2.0.0-beta.2, un usuario autenticado con permisos de edición de página puede inyectar un atributo de gestor de eventos JavaScript ejecutable en el HTML de imagen renderizado a través de la sintaxis de acción de medios Markdown de Grav. El problema es causado por los parámetros de consulta de imagen Markdown que se convierten en acciones de medios invocables. El método de medios público attribute() puede ser alcanzado de esta manera, permitiendo a un editor establecer un nombre y valor de atributo HTML arbitrarios en el elemento de imagen generado. Esta vulnerabilidad está corregida en 2.0.0-beta.2.

Information

Published : 2026-05-11 16:17

Updated : 2026-10-26 18:10

NVD link : CVE-2026-42841

Mitre link : CVE-2026-42841

CVE.ORG link : CVE-2026-42841

JSON object : View

Products Affected

getgrav

grav

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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