How severe is GHSA-q6v9-43v5-jv9q?

GHSA-q6v9-43v5-jv9q has a CVSS score of 6.2/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-q6v9-43v5-jv9q?

GHSA-q6v9-43v5-jv9q affects the following packages: CoreWCF.UnixDomainSocket (NuGet), CoreWCF.UnixDomainSocket (NuGet). Ecosystems affected: NuGet.

How do I fix GHSA-q6v9-43v5-jv9q?

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.

How do I detect GHSA-q6v9-43v5-jv9q in my NuGet dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for CoreWCF.UnixDomainSocket, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-q6v9-43v5-jv9q if there is no patch (or I can't update yet)?

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.

Is GHSA-q6v9-43v5-jv9q actively exploited in the wild?

No public exploit code has been indexed for GHSA-q6v9-43v5-jv9q yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-q6v9-43v5-jv9q?

GHSA-q6v9-43v5-jv9q has an EPSS (Exploit Prediction Scoring System) score of 0.1%, placing it in the 2th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-q6v9-43v5-jv9q?

GHSA-q6v9-43v5-jv9q is classified as CWE-362 (CWE-362), CWE-825 (CWE-825). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-q6v9-43v5-jv9q published, and has it been updated?

GHSA-q6v9-43v5-jv9q was published on June 19, 2026 and was last updated on June 19, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

.NET

.NET NuGet

Not in CISA KEV

MEDIUM severity

CoreWCF: UnixDomainSocket Non-Reentrant POSIX Identity ResolutionGHSA-q6v9-43v5-jv9q

MEDIUM

GHSA-q6v9-43v5-jv9q is a medium-severity (CVSS 6.2) CWE-362 vulnerability in CoreWCF.UnixDomainSocket. A fix is available for CoreWCF.UnixDomainSocket — see the affected versions and patch details below.

Also known asCVE-2026-54778

Published

Jun 19, 2026

Updated

Jun 19, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Oct 24, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-q6v9-43v5-jv9q.

EPSS Exploitation Probability

via FIRST.org ↗

0.1%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs2th percentile — riskier than 2% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

GHSA-q6v9-43v5-jv9q by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

2 pkgs affected

.NETCoreWCF.UnixDomainSocket.NETCoreWCF.UnixDomainSocket

Real-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

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`CoreWCF.UnixDomainSocket`	all versions	1.8.1`dotnet add package CoreWCF.UnixDomainSocket --version 1.8.1`
.NETNuGet	`CoreWCF.UnixDomainSocket`	≥ 1.9.0&&< 1.9.1	1.9.1`dotnet add package CoreWCF.UnixDomainSocket --version 1.9.1`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for CoreWCF.UnixDomainSocket, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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.

Frequently Asked Questions

### 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.