In March, Microsoft released cumulative security updates for Windows 10 and Windows 11, with support for certain versions continuing until March 2026. The updates include KB5079466 for Windows 11 version 26H1, KB5079473 for versions 24H2 and 25H2, KB5078883 for version 23H2, and KB5078885 for Windows 10 version 22H2. These updates will be distributed via Windows Update, the Microsoft Update Catalog, and WSUS for enterprise environments.
This month, Microsoft combined the Servicing Stack Update (SSU) with the Latest Cumulative Update, simplifying the update process. Key enhancements include improvements to Secure Boot, with expanded device target data for new certificates, and security enhancements for Explorer’s search functionality in Windows 11 versions 24H2 and 25H2. A fix for Windows Defender Application Control (WDAC) was also implemented, addressing issues with COM objects under certain policy configurations.
The Windows System Image Manager received a new warning dialog for confirming the trustworthiness of catalog files, which is important for enterprise environments. Updates for Windows 10 22H2, despite its end-of-life status, included fixes for secure boot issues and improvements for file version history in the Control Panel. An SSU for Windows 11 (KB5077869) was also released to maintain update stability.
Microsoft's updates scheduled for March 2026 will address vulnerabilities in components like the Windows App Installer, SQL Server, and Microsoft Office. The Security Update Guide provides detailed information on specific vulnerabilities and affected components.