CVE-2026-54780: Corewcf

Low severity, CVSS 3.7. EPSS: 0.2% chance of exploitation in the next 30 days.

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, the CoreWCF WS-Security 1.0 receive pipeline validates ds:SignedInfo SignatureMethod against the configured SecurityAlgorithmSuite but does not validate each ds:Reference DigestMethod, allowing a sender to use a rejected digest algorithm such as SHA-1 while the message is still accepted. This issue is fixed in versions 1.8.1 and 1.9.1.

Affected products

• Corewcf Corewcf: from 1.9.0, before 1.9.1 (fixed in 1.9.1); before 1.8.1 (fixed in 1.8.1)

Published 2026-07-08. Last modified 2026-07-09.