Summary
libcrux has All-Zero Key Generation Upon Catastrophic RNG Failure
The libcrux-ed25519 key generation samples Ed25519 secret keys from a provided CSPRNG in a loop for up to 100 attempts until a non-zero key is found. If a non-zero key could not be sampled within 100 attempts the key generation function would silently continue with an all-zero buffer as the secret key.
Mitigation
Instead of silently continuing with an all-zero signing key, starting from version 0.0.7 key generation will error in the case of 100 failed attempts at sampling a valid key.
Impact
This bug only occurs in the event of a catastrophic failure of the CSPRNG, but would allow anyone to forge signatures under the resulting static signing key.
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-434V-X5QV-PMH6? GHSA-434V-X5QV-PMH6 is a high-severity security vulnerability in libcrux-ed25519 (rust), affecting versions < 0.0.7. It is fixed in 0.0.7.
- Which versions of libcrux-ed25519 are affected by GHSA-434V-X5QV-PMH6? libcrux-ed25519 (rust) versions < 0.0.7 is affected.
- Is there a fix for GHSA-434V-X5QV-PMH6? Yes. GHSA-434V-X5QV-PMH6 is fixed in 0.0.7. Upgrade to this version or later.
- Is GHSA-434V-X5QV-PMH6 exploitable, and should I be worried? Whether GHSA-434V-X5QV-PMH6 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-434V-X5QV-PMH6 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-434V-X5QV-PMH6? Upgrade
libcrux-ed25519to 0.0.7 or later.