What’s Vulnerable › Vulnerabilities

CVE-2026-54778: CoreWCF: UnixDomainSocket Non-Reentrant POSIX Identity Resolution

• Severity: medium (CVSS 6.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-08 · updated 2026-07-09
• Weakness: CWE-362

Description

CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1, CoreWCF UnixDomainSocket POSIX peer identity resolution uses non-reentrant getpwuid and getgrgid calls, allowing concurrent connections to attribute one connection's identity to another or crash the host process under contention. This issue is fixed in versions 1.8.1 and 1.9.1.

Affected products

• CoreWCF: from 1.9.0, < 1.9.1; before 1.8.1

References

• https://github.com/CoreWCF/CoreWCF/commit/a3d95ea4627b818995e92c7def4c016164cacfce
• https://github.com/CoreWCF/CoreWCF/commit/b0acb105589b455a095ea5ff49f5191e4eeff791
• https://github.com/CoreWCF/CoreWCF/commit/b4867547c94bb088568935d581a55dda18a621e1
• https://github.com/CoreWCF/CoreWCF/releases/tag/v1.8.1
• https://github.com/CoreWCF/CoreWCF/releases/tag/v1.9.1
• https://github.com/CoreWCF/CoreWCF/security/advisories/GHSA-q6v9-43v5-jv9q

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