Microsoft Releases March 2026 Security Updates for Windows 11
Summary
Microsoft’s mandatory March 2026 Windows 11 updates include security patches, expanded Secure Boot certificate rollout, built-in Sysmon event logging, WDAC improvements, and reliability fixes.
Key points
- KB5079473 and KB5078883 update Windows 11 versions 25H2/24H2 and 23H2.
- The updates include March 2026 Patch Tuesday security patches; the article does not detail specific vulnerabilities.
- Microsoft says expanded device-targeting data will make more eligible systems receive Secure Boot certificates automatically.
- Built-in Sysmon can capture system events to Windows Event Log for threat detection; it is off by default and must be enabled.
- The update improves Windows Defender Application Control handling of COM objects.
- Microsoft fixed a File Explorer search reliability issue affecting searches across multiple drives.
Article Details
- Event Type
- Microsoft released mandatory March 2026 cumulative security updates for Windows 11.
- Impact
- KB5079473 and KB5078883 deliver security patches for vulnerabilities discovered in previous months, along with bug fixes and feature updates. Changes include broader automatic Secure Boot certificate rollout, built-in Sysmon for system-event logging (off by default), improved WDAC handling of COM objects, and more reliable File Explorer search. Microsoft reported no new known issues with the updates.
Vendors
Products
Windows 11Microsoft released mandatory March 2026 cumulative updates KB5079473 and KB5078883 for Windows 11 (25H2/24H2 and 23H2) to deliver security patches, bug fixes, and new features.Windows Defender Application Control (WDAC)The update improves Windows Defender Application Control (WDAC) handling of COM objects and fixes File Explorer search reliability across multiple drives.