CVE-2026-72702

Grav CMS before 2.0.16 contains an origin validation bypass in the Uri::referrer() and Pages::referrerRoute() methods, which validate the Referer header using an unanchored string prefix match (str_starts_with($referrer, $base)) with no trailing delimiter. An attacker who controls a domain that begins with the victim site's origin (e.g. https://example.com.attacker.tld) can send a request with such a Referer to be treated as same-origin, bypassing the Referer-based origin check.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-9ccq-2jfg-qw33
https://www.vulncheck.com/advisories/grav-cms-before-origin-validation-bypass-via-referer

Configurations

No configuration.

History

12 Oct 2026, 15:10

Type	Values Removed	Values Added
Summary		(es) Grav CMS anterior a la versión 2.0.16 contiene una omisión de validación de origen en los métodos Uri::referrer() y Pages::referrerRoute(), que validan el encabezado Referer utilizando una coincidencia de prefijo de cadena no anclada (str_starts_with($referrer, $base)) sin delimitador final. Un atacante que controla un dominio que comienza con el origen del sitio de la víctima (p. ej., HTTPS://example.com.attacker.tld) puede enviar una solicitud con dicho Referer para que sea tratado como del mismo origen, omitiendo la verificación de origen basada en Referer.

Information

Published : 2026-08-25 02:16

Updated : 2026-10-12 15:10

NVD link : CVE-2026-72702

Mitre link : CVE-2026-72702

CVE.ORG link : CVE-2026-72702

JSON object : View

Products Affected

No product.

CWE

CWE-346

Origin Validation Error

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