CVE-2026-54784

CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. In version 1.9.0, CoreWCF SPNEGO SecurityContextToken negotiation can expose the proof key recovered from the RSTR when TransportWithMessageCredential with Windows client credentials and session establishment are used, allowing an observer to impersonate the authenticated Windows principal and decrypt or forge WS-SecureConversation traffic. This issue is fixed in version 1.9.1.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/CoreWCF/CoreWCF/commit/2afae08b2fa5288428df89e8161116b816cf6b4b
https://github.com/CoreWCF/CoreWCF/commit/f216aa6929d41dc99cee098b1e69c260ec4c41c7
https://github.com/CoreWCF/CoreWCF/releases/tag/v1.9.1
https://github.com/CoreWCF/CoreWCF/security/advisories/GHSA-2288-8h3r-cqgg

Configurations

No configuration.

History

08 Jul 2026, 23:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-08 23:16

Updated : 2026-07-10 05:16

NVD link : CVE-2026-54784

Mitre link : CVE-2026-54784

CVE.ORG link : CVE-2026-54784

JSON object : View

Products Affected

No product.

CWE

CWE-311

Missing Encryption of Sensitive Data

CWE-523

Unprotected Transport of Credentials

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