GitHub Advisoryadvisory · NuGet

GHSA-2288-8h3r-cqgg CoreWCF: SPNEGO SecurityContextToken proof key wrapped without confidentiality

HIGH Published 2026-06-19 Modified 2026-06-19 Official page ↗
Aliases
CVE-2026-54784
Ecosystem
NuGet
Packages
CoreWCF.Primitives
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Weaknesses
CWE-311, CWE-523
Reviewed
2026-06-19

Affected packages

• NuGet CoreWCF.Primitives: >= 1.9.0, < 1.9.1 → fixed in 1.9.1

Description

Impact When the proof key recovered from the RSTR can be observed by a party that is not the legitimate client, that party can impersonate the authenticated Windows principal for the lifetime of the SCT (default ~10 hours) and decrypt or forge any subsequent WS‑SecureConversation traffic that uses keys derived from the SCT. Preconditions Using security mode TransportWithMessageCredential with client credential type Windows, along with session establishment (which triggers use of WS-SecureConversation). Patches Fixed in CoreWCF v1.9.1 Workarounds Ensure communication is protected by SSL/TLS to prevent capturing of SCT negotiation handshake.

Related

Alias · CVE (1)

  • CVE-2026-54784 CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. vulnerability

Weakness · CWE (2)

  • CWE-311 Missing Encryption of Sensitive Data weakness
  • CWE-523 Unprotected Transport of Credentials weakness

References