KB5041580: Addressing Security issues and improvements

August 13, 2024—KB5041580 (OS Builds 19044.4780 and 19045.4780)

Highlights

• This update addresses security issues for your Windows operating system.

Improvements
This security update includes quality improvements that were a part of update KB5040525 (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.

- [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.

- [Lock screen] This update addresses CVE-2024-38143. Because of this, the “Use my Windows user account” check box is not available on the lock screen to connect to Wi-Fi.

- [NetJoinLegacyAccountReuse] This update removes this registry key. For more information refer to KB5020276—Netjoin: Domain join hardening changes.

- [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.