VULNERABILITY INTELLIGENCE
CVE-2026-54781
CVSS score7.4 HIGH
EPSS probability0.25%
CISA KEVNot currently listed
Published2026-07-08
Last modified2026-07-09
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. Prior to 1.8.1 and 1.9.1, CoreWCF SAML token validation does not enforce SubjectConfirmation method URIs or holder-of-key proof keys in SamlSecurityTokenHandler, allowing holder-of-key downgrade or custom confirmation method assertions to authenticate a subject without proving authority over the assertion. This issue is fixed in versions 1.8.1 and 1.9.1.
Weakness classification
- security-advisories@github.com: CWE-287