August 13, 2024—KB5041585 (OS Builds 22621.4037 and 22631.4037)
Applies To
Windows 11 version 22H2, all editions Windows 11 version 23H2, all editionsRelease Date:
8/13/2024
Version:
OS Builds 22621.4037 and 22631.4037
07/09/24---END OF SERVICE NOTICE---
IMPORTANT Home and Pro editions of Windows 11, version 22H2 will reach end of service on October 8, 2024. Until then, these editions will only receive security updates. They will not receive non-security, preview updates. To continue receiving security and non-security updates after October 8, 2024, we recommend that you update to the latest version of Windows.
Note We will continue to support Enterprise and Education editions after October 8, 2024.
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 11, version 23H2, see its update history page.
Note Follow @WindowsUpdate to find out when new content is published to the Windows release health dashboard.
Highlights
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This update addresses security issues for your Windows operating system.
Improvements
Note: To view the list of addressed issues, click or tap the OS name to expand the collapsible section.
Important: Use EKB KB5027397 to update to Windows 11, version 23H2.
This security update includes quality improvements. Key changes include:
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This build includes all the improvements in Windows 11, version 22H2.
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No additional issues are documented for this release.
This security update includes improvements that were a part of update KB5040527 (released July 23, 2024). 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.
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[BitLocker (known issue)] A BitLocker recovery screen shows when you start up your device. This occurs after you install the July 9, 2024, update. This issue is more likely to occur if device encryption is on. Go to Settings > Privacy & Security > Device encryption. To unlock your drive, Windows might ask you to enter the recovery key from your Microsoft account.
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[Lock screen] This update addresses CVE-2024-38143. Because of this, the “Use my Windows user account” checkbox is not available on the lock screen to connect to Wi-Fi.
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[NetJoinLegacyAccountReuse] This update removes this registry key. For more information refer to KB5020276—Netjoin: Domain join hardening changes.
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[Secure Boot Advanced Targeting (SBAT) and Linux Extensible Firmware Interface (EFI)] This update applies SBAT to systems that run Windows. This stops vulnerable Linux EFI (Shim bootloaders) from running. This SBAT update will not apply to systems that dual-boot Windows and Linux. After the SBAT update is applied, older Linux ISO images might not boot. If this occurs, work with your Linux vendor to get an updated ISO image.
If you installed earlier updates, only the new updates contained in this package will be downloaded and installed on your device.
For more information about security vulnerabilities, please refer to the Security Update Guide website and the August 2024 Security Updates.
Windows 11 servicing stack update (KB5041584) - 22621.4027 and 22631.4027
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
|
Applies to |
Symptom |
Workaround |
|---|---|---|
|
All users |
After installing this security update, you might face issues with booting Linux if you have enabled the dual-boot setup for Windows and Linux in your device. Resulting from this issue, your device might fail to boot Linux and show the error message “Verifying shim SBAT data failed: Security Policy Violation. Something has gone seriously wrong: SBAT self-check failed: Security Policy Violation.” The August 2024 Windows security update applies a Secure Boot Advanced Targeting (SBAT) setting to devices that run Windows to block old, vulnerable boot managers. This SBAT update will not be applied to devices where dual booting is detected. On some devices, the dual-boot detection did not detect some customized methods of dual-booting and applied the SBAT value when it should not have been applied. |
The September 2024 Windows security update (KB5043076) and later updates do not contain the settings that caused this issue. On Windows-only systems, after installing the September 2024 or later updates, you can set the registry key documented in CVE-2022-2601 and CVE-2023-40547 to ensure the SBAT security update is applied. On systems that dual-boot Linux and Windows, there are no additional steps necessary after installing the September 2024 or later updates. |
How to get this update
Before you install this update
Microsoft 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 update
To install this update, use one of the following Windows and Microsoft release channels.
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Available |
Next Step |
|
Yes |
None. This update will be downloaded and installed automatically from Windows Update and Microsoft Update. |
|
Available |
Next Step |
|
Yes |
None. This update will be downloaded and installed automatically from Windows Update for Business in accordance with configured policies. |
|
Available |
Next Step |
|
Yes |
To get the standalone package for this update, go to the Microsoft Update Catalog website. |
|
Available |
Next Step |
|
Yes |
This update will automatically sync with Windows Server Update Services (WSUS) if you configure Products and Classifications as follows: Product: Windows 11 Classification: Security Updates |
If you want to remove the LCU
To 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 information
For a list of the files that are provided in this update, download the file information for cumulative update 5041585.
For a list of the files that are provided in the servicing stack update, download the file information for the SSU (KB5041584) - versions 22621.4027 and 22631.4027.
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