Summary
libcrux-ml-dsa: Signature Verification on AVX2 Platforms Mishandles Edge Case
The AVX2 implementation of ML-DSA verification incorrectly implemented
the use_hint function, mishandling an edge case that should lead to
signature rejection.
Mitigation
From version 0.0.9 the edge case is handled correctly and invalid
signatures are rejected.
Impact
An attacker could make the ML-DSA verifier accept a crafted invalid
signature under a maliciously generated verification key, if the AVX2
implementation is used.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is GHSA-FHVH-VW7H-9XF3? GHSA-FHVH-VW7H-9XF3 is a high-severity security vulnerability in libcrux-ml-dsa (rust), affecting versions < 0.0.9. It is fixed in 0.0.9.
- Which versions of libcrux-ml-dsa are affected by GHSA-FHVH-VW7H-9XF3? libcrux-ml-dsa (rust) versions < 0.0.9 is affected.
- Is there a fix for GHSA-FHVH-VW7H-9XF3? Yes. GHSA-FHVH-VW7H-9XF3 is fixed in 0.0.9. Upgrade to this version or later.
- Is GHSA-FHVH-VW7H-9XF3 exploitable, and should I be worried? Whether GHSA-FHVH-VW7H-9XF3 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-FHVH-VW7H-9XF3 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-FHVH-VW7H-9XF3? Upgrade
libcrux-ml-dsato 0.0.9 or later.