February 13, 2024—KB5034770 (OS Build 20348.2322)

Improvements

This security update includes quality improvements. When you install this KB:

• This update addresses an issue that affects remote direct memory access (RDMA) performance counters. They do not return networking data on VMs in the right way.

• This update addresses an issue that affects fontdrvhost.exe. It stops responding when you use Compact Font Format version 2 (CFF2) fonts.

• This update addresses a memory leak in ctfmon.exe.

• This update addresses a memory leak in TextInputHost.exe.

• This update addresses an issue that affects protected content. It stops cross-process windows from being created. Because of this update, you can keep using out-of-process hosting for things like WebView2 under protected, top-level windows.

• This update addresses an issue that affects touchscreens. They do not work properly when you use more than one monitor.

• This update addresses an issue that affects Windows Defender Application Control (WDAC). Its “allow” policies might block some binaries from running.

• This update affects Unified Extensible Firmware Interface (UEFI) Secure Boot systems. It adds a renewed signing certificate to the Secure Boot DB variable. You can now opt for this change. For more details, see KB5036210.

• This update addresses an issue that affects the download of device metadata. Downloads from the Windows Metadata and Internet Services (WMIS) over HTTPS are now more secure.

• This update addresses an issue that affects the Local Security Authority Subsystem Service (LSASS). It might stop working. This occurs when you access the Active Directory database.

• This update includes quarterly changes to the Windows Kernel Vulnerable Driver Blocklist file, DriverSiPolicy.p7b. It adds to the list of drivers that are at risk for Bring Your Own Vulnerable Driver (BYOVD) attacks.

• This update addresses an issue that affects the Certificate Authority snap-in. You cannot select the "Delta CRL" option. This stops you from using the GUI to publish Delta CRLs.

• This update addresses an issue that affects a local account. You cannot sign in to an account that Windows LAPS manages. This occurs if you set the "Require Smart Card for Interactive Logon" policy.

• This update addresses an issue that affects Server Message Block (SMB) connections. They disconnect when all of the following are true:

  • You change the client and server encryption cipher list from the default values.

  • The client and server do not have any ciphers in common.

  • SMB encryption is not in use.

  • A multi-channel configuration, such as RDMA, is in place.

• The update addresses an issue that affects SMB over a Quick UDP Internet Connection (QUIC). It stops responding if port 445 is blocked.

• This update changes a setting in Active Directory Users & Computers. By default, the snap-in now uses a strong certificate mapping of X509IssuerSerialNumber. It does not use the weak mapping of x509IssuerSubject.

• This update addresses a known issue that affects chromium-based internet browsers, such as Microsoft Edge. They might not open correctly. They might also show a white screen and stop responding when you open them. Devices that have browser-specific Image File Execution Options (IFEO) might also encounter this issue. Also, when an entry for a chromium-based browser is in the Windows registry, the issue might occur.

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 and the February 2024 Security Updates.

Known issues in this update

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

How to get this update

Before installing this update

Microsoft 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.

Prerequisite for offline OS image servicing:

​​​​​​​Make sure that your image includes KB5030216 (09/12/2023) or a later LCU. If not, install it on your offline media before you install the latest update. This LCU updates the SSU version to 20348.1960. That is the minimum SSU version you must have to prevent error 0x800f0823 (CBS_E_NEW_SERVICING_STACK_REQUIRED).

Install this update

File Information

For a list of the files that are provided in this update, download the file information for cumulative update 5034770. 

For a list of the files that are provided in the servicing stack update, download the file information for the SSU - version 20348.2305.