VULNERABILITY INTELLIGENCE

CVE-2026-54784

CVSS score7.4 HIGH
EPSS probability0.27%
CISA KEVNot currently listed
Published2026-07-08
Last modified2026-07-10
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Description

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.

Weakness classification

  • security-advisories@github.com: CWE-311

Primary references