CVE-2026-54782

CVE-2026-54782: critical vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2026-54782CVSS 10.0Windows

CVE-2026-54782

CVE-2026-54782: critical vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
10.0 CRITICAL
EPSS
34.24%
Known exploited
not in KEV
Product
-

What is known

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.

Business impact

Successful exploitation of CVE-2026-54782, a critical vulnerability (CVSS 10.0) affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

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