GHSA-5c9c-6x87-f9vm
HIGHGHSA-5c9c-6x87-f9vm is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in zstd. O3 Security confirms whether GHSA-5c9c-6x87-f9vm is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
zstd vulnerable to buffer overrun
Blast Radius
zstd📦github.com/facebook/zstdReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI, SwiftURL packages — download data is not available via public APIs for these ecosystems.
Description
A vulnerability was found in zstd v1.4.10, where an attacker can supply an empty string as an argument to the command line tool to cause buffer overrun.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | zstd | all versions | 1.5.4.0 |
| 📦SwiftURL | github.com/facebook/zstd | all versions | 1.5.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for zstd. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update zstd to 1.5.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5c9c-6x87-f9vm is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-5c9c-6x87-f9vm is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-5c9c-6x87-f9vm. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-5c9c-6x87-f9vm in your dependencies?
O3 detects GHSA-5c9c-6x87-f9vm across PyPI, SwiftURL dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.