CVE-2026-72701 (GCVE-0-2026-72701)
Vulnerability from cvelistv5 – Published: 2026-08-25 01:30 – Updated: 2026-08-25 01:30
VLAI
EPSS
VEX
Title
Grav CMS before 2.0.16 Timing Attack via verifyNonce
Summary
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.
Severity
CWE
- CWE-208 - Observable Timing Discrepancy
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/getgrav/grav/security/advisori… | vendor-advisory |
| https://www.vulncheck.com/advisories/grav-cms-bef… | third-party-advisory |
Impacted products
Date Public
2026-08-10 00:00
{
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"product": "grav",
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"baseScore": 6.3,
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"providerMetadata": {
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],
"url": "https://github.com/getgrav/grav/security/advisories/GHSA-38p6-h87p-r4cg"
},
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],
"url": "https://www.vulncheck.com/advisories/grav-cms-before-timing-attack-via-verifynonce"
}
],
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"dateReserved": "2026-08-10T13:02:20.829Z",
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"state": "PUBLISHED"
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"vulnerability-lookup:meta": {
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}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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