https://www.bleepingcomputer.com/news/microsoft/windows-10-kb5016616-and-kb5016623-updates-released/

Microsoft has released the Windows 10 KB5016616 and KB5016623 cumulative updates for versions 21H2, version 21H1, version 20H2, and 1809 to fix security vulnerabilities and resolve bugs and performance issues.

This update is not available for Windows 10 1909 or Windows 10 2004.