CVE-2026-54784EPSS p17.8%

CVE-2026-54784CVE-2026-54784

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.

Scoring

CVSS 7.4 ()
VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS0.27% probability of exploitation · percentile 17.8% · 2026-10-05T12:00:23Z
Last modified2026-07-10
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.