This article describes the protection against the publicly disclosed Secure Boot security feature bypass that uses the BlackLotus UEFI bootkit tracked by CVE-2023-24932, how to enable the mitigations, and guidance on bootable media.

The Windows Malicious Software Removal Tool (MSRT) helps remove malicious software from computers that are running any of the following operating systems: Windows 11. Windows Server 2022. Windows 10. Windows Server 2019. Windows Server 2016. Windows 8.1. Windows Server 2012 R2. Windows Server 2008 R2. Windows 7. Windows Server 2008.

Key changes include the following: Windows devices that has Unified Extensible Firmware Interface (UEFI) based firmware can run with Secure Boot enabled. The Secure Boot Forbidden Signature Database (DBX) prevents UEFI modules from loading. This update adds modules to the DBX. A security feature bypass vulnerability exists in secure boot.

To help keep Windows devices secure, Microsoft adds vulnerable bootloader modules to the Secure Boot DBX revocation list (maintained in the system UEFI-based firmware) to invalidate the vulnerable modules.

Windows updates released on and after February 13, 2024 include the ability to apply the Windows UEFI CA 2023 certificate to UEFI Secure Boot Allowed Signature Database (DB). Updating the DB will enable devices to receive future boot loader updates that are included in monthly updates.

The .NET Framework Repair Tool provides an option to repair the versions of .NET Framework that are installed on the computer (step 3 of the process in the "Repair Tool options" section). The tool requires the redistributable files of those versions to be available at the time of repair.

What problem does this troubleshooter address? Some devices that installed the April 25, 2022, update KB5012643 for Windows 11, version 21H2, are unable to run .NET Framework applications.

NET 8.0 has been refreshed with the latest update as of August 13, 2024. This update contains both security and non-security fixes. See the release notes for details on updated packages.

When you recompile a Microsoft .NET Framework 4.5.1 application that uses .NET portable libraries to target the Microsoft .NET Framework 4.5.2, you receive the following error message during compilation: The type ' {type} ' is defined in an assembly that is not referenced.

Regsvr32 is a command-line utility to register and unregister OLE controls, such as DLLs and ActiveX controls in the Windows Registry. Regsvr32.exe is installed in the %systemroot%\System32 folder in Windows XP and later versions of Windows.