CVE-2026-54774

Summary

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, SamlSerializer skips final SignatureValue verification when a CoreWCF service validates SAML tokens using a non-X.509 signing token, allowing an attacker to reference a non-X.509 SecurityToken key identifier and bypass assertion signature verification. This issue is fixed in versions 1.8.1 and 1.9.1.

Affected Software

VendorProductVersion RangeStatus
CoreWCFCoreWCF>= 1.9.0, < 1.9.1affected
CoreWCFCoreWCF< 1.8.1affected

Weaknesses

  • CWE-345: CWE-345: Insufficient Verification of Data Authenticity
  • CWE-347: CWE-347: Improper Verification of Cryptographic Signature

References