CVE-2026-72701
Grav CMS before 2.0.16 Timing Attack via verifyNonce
- State
- Published
- Severity
- 6.3 Medium
- Published
- Aug 25, 2026
- Updated
- Oct 8, 2026
- Reserved
- Aug 10, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.3 Medium | 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 | VulnCheck |
| 3.1 | 3.7 Low | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N | VulnCheck |
Weaknesses
- CWE-208 Observable Timing Discrepancy
Affected Products
| Product | Versions |
|---|---|
gravgetgrav |
|
References
- GitHub Security Advisory (GHSA-38p6-h87p-r4cg)vendor-advisory
- VulnCheck Advisory: Grav CMS before 2.0.16 Timing Attack via verifyNoncethird-party-advisory
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.