Low severity · published Aug 25, 2026
CVE-2026-72701
Grav CMS before 2.0.16 Timing Attack via verifyNonce
3.7
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 12% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GR
grav · getgrav
before 2.0.16 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-72701
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-72701
vendor-advisory
https://github.com/getgrav/grav/security/advisories/GHSA-38p6-h87p-r4cg
third-party-advisory
https://www.vulncheck.com/advisories/grav-cms-before-timing-attack-via-verifynonce
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