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CVE-2026-72701 (GCVE-0-2026-72701)

Vulnerability from cvelistv5 – Published: 2026-08-25 01:30 – Updated: 2026-08-27 14:54
VLAI
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.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-27 14:53 UTC
CWE
  • CWE-208 - Observable Timing Discrepancy
References
Impacted products
Vendor Product Version CPE status
getgrav grav Affected: 0 , < 2.0.16 (semver)
Unaffected: 2.0.16 (semver)
    cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-10 00:00
Show details on NVD website

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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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Detection rules are retrieved from Rulezet.

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Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


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