Microsoft security advisory (AV26-377) – Canadian Centre for Cyber Security

Serial number: AV26-377
Date: April 22, 2026

On April 21, 2026, Microsoft published an out-of-band (OOB) security update to address a critical vulnerability in the following product:

• .NET 10.0.0 – versions 10.0.0 to 10.0.6

The Cyber Centre encourages users and administrators to review the web links provided and apply the necessary update.