CVE-2026-72701

Grav CMS before 2.0.16 contains a timing vulnerability in Utils::verifyNonce() that uses non-constant-time string comparison with the === operator instead of hash_equals() for CSRF nonce validation. Attackers can measure response timing differences to recover valid nonce values byte-by-byte through multiple requests, weakening CSRF protection below its intended security margin.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-38p6-h87p-r4cg
https://www.vulncheck.com/advisories/grav-cms-before-timing-attack-via-verifynonce
https://github.com/getgrav/grav/security/advisories/GHSA-38p6-h87p-r4cg

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 vulnerabilidad de temporización en Utils::verifyNonce() que utiliza una comparación de cadenas de tiempo no constante con el operador === en lugar de hash_equals() para la validación de nonces CSRF. Los atacantes pueden medir las diferencias de tiempo de respuesta para recuperar valores de nonce válidos byte a byte a través de múltiples solicitudes, debilitando la protección CSRF por debajo de su margen de seguridad previsto.

Information

Published : 2026-08-25 02:16

Updated : 2026-10-12 15:10

NVD link : CVE-2026-72701

Mitre link : CVE-2026-72701

CVE.ORG link : CVE-2026-72701

JSON object : View

Products Affected

No product.

CWE

CWE-208

Observable Timing Discrepancy

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