SAML Token Signature Verification Bypass in CoreWCF by CoreWCF
CVE-2026-54774

7.4HIGH

Key Information:

Vendor

Corewcf

Status
Corewcf
Vendor
CVE Published:
8 July 2026

What is CVE-2026-54774?

A flaw in CoreWCF allows the SamlSerializer to bypass final SignatureValue verification when validating SAML tokens with non-X.509 signing tokens. This weakness enables attackers to refer to a non-X.509 SecurityToken key identifier, which can compromise the integrity of assertion signature verification. Users of CoreWCF should upgrade to versions 1.8.1 or 1.9.1 to mitigate this vulnerability.

Affected Version(s)

CoreWCF >= 1.9.0, < 1.9.1 < 1.9.0, 1.9.1

CoreWCF < 1.8.1 < 1.8.1

References

https://github.com/CoreWCF/CoreWCF/security/advisories/GH...
x_refsource_CONFIRM
https://github.com/CoreWCF/CoreWCF/commit/65d09022749854b...
x_refsource_MISC
https://github.com/CoreWCF/CoreWCF/commit/b914495ce63c449...
x_refsource_MISC

CVSS V3.1

Score:
7.4
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.