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.
History

Thu, 27 Aug 2026 18:00:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 25 Aug 2026 02:00:00 +0000

Type Values Removed Values Added
Description 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.
Title Grav CMS before 2.0.16 Timing Attack via verifyNonce
First Time appeared Getgrav
Getgrav grav
Weaknesses CWE-208
CPEs cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
Vendors & Products Getgrav
Getgrav grav
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 6.3, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-08-25T01:30:23.965Z

Updated: 2026-08-27T14:54:28.112Z

Reserved: 2026-08-10T13:02:20.829Z

Link: CVE-2026-72701

cve-icon Vulnrichment

Updated: 2026-08-27T14:53:45.824Z

cve-icon NVD

Status : Deferred

Published: 2026-08-25T02:16:45.980

Modified: 2026-08-31T20:52:56.343

Link: CVE-2026-72701

cve-icon Redhat

No data.