CVE-2026-54782
Published:July 08, 2026
Updated:July 21, 2026
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 1.1 and SAML 2.0 token validation does not correctly resolve the issuer signing key or require signed tokens when IdentityConfiguration is used with federated bindings, allowing an unauthenticated remote attacker to impersonate any principal the trusted STS could issue. This issue is fixed in versions 1.8.1 and 1.9.1.
Affected Packages
corewcf.primitives (DOT_NET):
Affected version(s) >=0.1.0.8 <1.8.1Fix Suggestion:
Update to version 1.8.1https://github.com/CoreWCF/CoreWCF.git (GITHUB):
Affected version(s) >=v0.3.0 <v1.8.1Fix Suggestion:
Update to version v1.8.1https://github.com/CoreWCF/CoreWCF.git (GITHUB):
Affected version(s) =v1.9.0 <v1.9.1Fix Suggestion:
Update to version v1.9.1corewcf.primitives (NUGET):
Affected version(s) =1.9.0 <1.9.1Fix Suggestion:
Update to version 1.9.1corewcf.primitives (NUGET):
Affected version(s) >=0.1.0-preview <1.8.1Fix Suggestion:
Update to version 1.8.1Related Resources (7)
Do you need more information?
Contact UsCVSS v4
Base Score:
9.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
HIGH
Subsequent System Integrity
HIGH
Subsequent System Availability
NONE
CVSS v3
Base Score:
10
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
EPSS
Base Score:
0.25