CVE-2026-54774 (GCVE-0-2026-54774)

Vulnerability from cvelistv5 – Published: 2026-07-08 22:17 – Updated: 2026-07-10 03:55
VLAI
Title
CoreWCF: SamlSerializer skips SignatureValue verification when SAML signing token is not an X.509 certificate
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.
Severity
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-09 00:00 UTC
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
References
Impacted products
Vendor Product Version CPE status
CoreWCF CoreWCF Affected: >= 1.9.0, < 1.9.1
Affected: < 1.8.1
guessed Create a notification for this product.
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