GHSA-q6v9-43v5-jv9q
MEDIUMCoreWCF: UnixDomainSocket Non-Reentrant POSIX Identity Resolution
Blast Radius
CoreWCF.UnixDomainSocket.NETCoreWCF.UnixDomainSocketReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Race condition in POSIX peer identity resolution may attribute one connection’s identity to another (getpwuid/getgrgid non-reentrant) and may crash the host process under contention.
Patches
Fixed in CoreWCF v1.8.1 and v1.9.1
Workarounds
Restrict UDS filesystem permissions so that only trusted local users can connect to the socket path. The race still exists but the attacker pool is constrained.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | CoreWCF.UnixDomainSocket | all versions | 1.8.1 |
| .NETNuGet | CoreWCF.UnixDomainSocket | ≥ 1.9.0&&< 1.9.1 | 1.9.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for CoreWCF.UnixDomainSocket. 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 CoreWCF.UnixDomainSocket to 1.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-q6v9-43v5-jv9q 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-q6v9-43v5-jv9q 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-q6v9-43v5-jv9q. 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-q6v9-43v5-jv9q in your dependencies?
O3 detects GHSA-q6v9-43v5-jv9q across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.