CVE-2026-54778: medium-severity vulnerability in CoreWCF
CoreWCF: UnixDomainSocket Non-Reentrant POSIX Identity Resolution
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.2epss 0.1%
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.
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
Affected products
CoreWCF · CoreWCFRelated CVEs — CoreWCF
In the same product, most dangerous first.
CVE-2026-54772HIGHCoreWCF: Pre-authentication infinite-loop CPU exhaustion in CoreWCF net.tcp / net.pipe / net.uds framing handshakeEPSS 0.8%CVE-2026-54775MEDIUMCoreWCF: Kafka consume pump halts permanently on a Kafka tombstone (null-value record), causing persistent endpoint denial of service.EPSS 0.6%CVE-2024-28252HIGHCoreWCF NetFraming based services can leave connections open when they should be closedEPSS 0.6%CVE-2026-54779MEDIUMCoreWCF: SAML token replay protection is inoperativeEPSS 0.4%CVE-2026-54782CRITICALCoreWCF: Authentication bypass in CoreWCF SAML 1.1 / 2.0 token signature validationEPSS 0.4%CVE-2026-54773MEDIUMCoreWCF: WS-Security signature substitution via document-wide Signature lookupEPSS 0.4%
References
https://github.com/CoreWCF/CoreWCF/commit/a3d95ea4627b818995e92c7def4c016164cacfcehttps://github.com/CoreWCF/CoreWCF/commit/b0acb105589b455a095ea5ff49f5191e4eeff791https://github.com/CoreWCF/CoreWCF/commit/b4867547c94bb088568935d581a55dda18a621e1https://github.com/CoreWCF/CoreWCF/releases/tag/v1.8.1https://github.com/CoreWCF/CoreWCF/releases/tag/v1.9.1https://github.com/CoreWCF/CoreWCF/security/advisories/GHSA-q6v9-43v5-jv9q