CVE-2026-54782: Authentication Bypass by Spoofing

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 SAML 1.1 and SAML 2.0 token validation does not correctly resolve the issuer signing key or require signed tokens when IdentityConfiguration is used with federated binding...

GHSA-XJR9-GG9Q-JX3V CoreWCF: Authentication bypass in CoreWCF SAML 1.1 / 2.0 token signature validation

Impact Full impersonation of any principal the trusted STS could have issued an assertion for — including administrative principals when the relying party grants them via SAML claims. Affects both SAML 1.1 and SAML 2.0. Preconditions Relying-party service is hosted with WSFederationHttpBinding or...