CVE-2026-54782 | BDVDB-2026-346243 Detail

CoreWCFCoreWCF

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 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.

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact none. Attack vector: network.

Weaknesses#

CWE-290 Authentication Bypass by Spoofing
CWE-347 Improper Verification of Cryptographic Signature

References#

Exploit#

No public exploit known

History#

Version 12026-07-08Record published in the CVE List.
Version 22026-07-10Most recent update recorded in the CVE List.

Published

Published: 2026-07-08
Last modified: 2026-07-10

Vendor information

Vendor: CoreWCF
Product: CoreWCF

All CoreWCF vulnerabilities

Score

10.0 Critical

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 36.1.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Not classified

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
>= 1.9.0, < 1.9.1
Fixed
Not stated
Vulnerable
< 1.8.1
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

10.0 Critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	None
User Interaction	None
Scope	Changed
Confidentiality	High
Integrity	High
Availability	None

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).