September 10, 2024—KB5043055 (OS Build 25398.1128)

For information about Windows update terminology, see the article about the types of Windows updates and the monthly quality update types. For an overview of Windows Server, version 23H2, see its update history page.

Improvements

This security update includes quality improvements. Below is a summary of the key issues that this update addresses when you install this KB. If there are new features, it lists them as well. The bold text within the brackets indicates the item or area of the change we are documenting.

• [Windows Installer] When it repairs an application, the User Account Control (UAC) does not prompt for your credentials. After you install this update, the UAC will prompt for them. Because of this, you must update your automation scripts. Application owners must add the Shield icon. It indicates that the process requires full administrator access. To turn off the UAC prompt, set theHKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Installer\DisableLUAInRepairregistry value to1. The changes in this update might affect automatic Windows Installer repairs; see Application Resiliency: Unlock the Hidden Features of Windows Installer.
• [BitLocker] You might not be able to decrypt a BitLocker data drive. This occurs when you move that drive from a newer version of Windows to an older version.
• [Unified Write Filter (UWF) Windows Management Instrumentation (WMI)] API calls to them to shut down or restart a system throws an access denied exception.
• [Azure Virtual Desktop] A deadlock stops you from signing in to sessions.
  For more information about security vulnerabilities, please refer to the Security Update Guide and the September 2024 Security Updates.

Windows Server, version 23H2 servicing stack update (KB5043107) - 25398.1128

This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. Servicing stack updates (SSU) ensure that you have a robust and reliable servicing stack so that your devices can receive and install Microsoft updates.

Known issues in this update

Microsoft is not currently aware of any issues with this update.

How to get this update

Before you install this updateMicrosoft now combines the latest servicing stack update (SSU) for your operating system with the latest cumulative update (LCU). For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.Install this updateTo install this update, use one of the following Windows and Microsoft release channels.

Windows UpdateBusinessCatalogServer Update Services

If you want to remove the LCUTo remove the LCU after installing the combined SSU and LCU package, use the DISM/Remove-Package command line option with the LCU package name as the argument. You can find the package name by using this command:DISM /online /get-packages.Running Windows Update Standalone Installer (wusa.exe) with the**/uninstall **switch on the combined package will not work because the combined package contains the SSU. You cannot remove the SSU from the system after installation.

File InformationFor a list of the files that are provided in this update, download the file information for cumulative update 5043055.For a list of the files that are provided in the servicing stack update, download the file information for the SSU (KB5043107) - version 25398.1128.