CVE-2026-54774

CoreWCF: SamlSerializer skips SignatureValue verification when SAML signing token is not an X.509 certificate

State
Published
Severity
7.4 High
Published
Jul 8, 2026
Updated
Jul 10, 2026
Reserved
Jun 15, 2026

Read the record on cve.org

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, 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.

Scores

CVSSScoreVectorSource
3.17.4 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NGitHub_M

Weaknesses

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

Affected Products

ProductVersions
CoreWCFCoreWCF
  • >= 1.9.0, < 1.9.1Affected
  • < 1.8.1Affected

References

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