Summary
fast-float has multiple soundness issues
fast-float contains multiple soundness issues:
- Undefined behavior when checking input length, which has been merged but no package pubished.
- Many functions marked as safe with non-local safety guarantees
The library is also unmaintained.
Alternatives
For quickly parsing floating-point numbers third-party crates are generally no longer needed. A fast float parsing algorithm by the author of lexical has been merged into libcore. When requiring direct parsing from bytes and/or partial parsers, the fast-float2 fork of fast-float containing these security patches and reduces overall usage of unsafe.
Impact
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-X8JH-XJ3X-GX3C? GHSA-X8JH-XJ3X-GX3C is a low-severity security vulnerability in fast-float (rust), affecting versions <= 0.2.0. No fixed version is listed yet.
- Which versions of fast-float are affected by GHSA-X8JH-XJ3X-GX3C? fast-float (rust) versions <= 0.2.0 is affected.
- Is there a fix for GHSA-X8JH-XJ3X-GX3C? No fixed version is listed for GHSA-X8JH-XJ3X-GX3C yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is GHSA-X8JH-XJ3X-GX3C exploitable, and should I be worried? Whether GHSA-X8JH-XJ3X-GX3C 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-X8JH-XJ3X-GX3C 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.