GitHub Advisoryadvisory · NuGet

GHSA-rpj7-hr7h-w6p9 CoreWCF: SamlSerializer skips SignatureValue verification when SAML signing token is not an X.509 certificate

HIGH Published 2026-06-19 Modified 2026-06-19 Official page ↗
Aliases
CVE-2026-54774
Ecosystem
NuGet
Packages
CoreWCF.Primitives
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Weaknesses
CWE-345, CWE-347
Reviewed
2026-06-19

Affected packages

• NuGet CoreWCF.Primitives: < 1.8.1 → fixed in 1.8.1 • NuGet CoreWCF.Primitives: >= 1.9.0, < 1.9.1 → fixed in 1.9.1

Description

Impact When a service is configured to validate SAML tokens using a method other than X.509 certificate signing, the final signature verification is skipped. Preconditions The service is configured to authenticate using SAML tokens and an out of band token resolver (commonly the IssuerTokenResolver of IssuedTokenServiceCredential) holds a non-X.509 SecurityToken whose key identifier the attacker can reference in the assertion’s `` - for example a `BinarySecretSecurityToken` representing the symmetric proof key issued by a WS-Trust symmetric-key holder-of-key STS. Patches Fixed in CoreWCF v1.8.1 and v1.9.1 Workarounds None

Related

Alias · CVE (1)

  • CVE-2026-54774 CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. vulnerability

Weakness · CWE (2)

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

References