Windows 10 KB5078885 ESU out with Secure Boot 2023, replacing expiring Secure Boot certificates from 2011. But it's a staged roll out.

Microsoft confirms systems without updated Secure Boot certificates will boot normally but lose some security protections.

How to check your Windows PC for expiring security certificates - a big one is ending soon ...

In June 2025, Microsoft announced that, in June 2026, it would begin deprecating Secure Boot certificates of Windows systems from 2011, which were superseded by their 2023 counterparts.

Microsoft has released the Windows 10 KB5078885 extended security update to fix the March 2026 Patch Tuesday vulnerabilities, ...

TL;DR: Secure Boot certificates in Windows 10 and 11 will expire by June 2026, risking system security and compatibility. Microsoft is issuing new certificates through updates and OEM firmware ...

Microsoft is rolling out "Secure Boot Allowed Key Exchange Key (KEK) Update," which requires a system reboot to finish ...