Microsoft releases KP5004945 for Windows 10 version 2004, 20h2 and 21h1 ›OS Built 19041.1083, 19042.1083 and 19043.1083 Out-band

Microsoft released an unplanned update for Windows 10 version 21H1, version 20H2 and version 2004 on Wednesday night. Microsoft has fixed the security vulnerability with an upgrade outside of KP5004945 CVE-2021-34527 On the Windows Print Spoiler service. After installing this and subsequent updates, non-admin users can only install signed printer drivers on the print server. By default, administrators can install both signed and unsigned printer drivers on the print server. Microsoft recommends that you immediately install this update on all supported Windows clients and servers, starting with devices that currently offer print server roles. The update generates 19041.1083, 19042.1083 and 19043.1083 for the Windows 10 OS, and can now be downloaded from the Windows Update, Microsoft Update, Windows Server Update Services or Microsoft Update list. To use this update, you must install the KB5003173 update from May 11, 2021. More information about this update for Windows 10 can be found below or through Microsoft.

Download -> Download the KB5004945 update for Windows 10

You can download KB5004945 for Windows 10 directly from Microsoft:

The update includes the following improvements and bug fixes:

As documented in CVE-2021-34527, remote code activation on a Windows print spoiler service called “Print Nightmare” refers to exploitation. After installing this and later Windows updates, non-admin users can only install signature print drivers on the print server. By default, administrators can install both signed and unsigned printer drivers on the print server. Root certificates installed on the system’s trusted root certificate authorities trust the signed drivers. Microsoft recommends that you immediately install this update on all supported Windows client and server operating systems, starting with devices that currently offer print server role. You have the option to configure the RestrictDriverInstallationToAd Administrators Registration system to prevent non-administrators from installing signature printer drivers on the print server. For more information, see KB5005010.

More information about KB5004945 for Windows 10 can be found here Microsoft.

CVE-2021-34527 | Vulnerability in Windows Ax spooler remote code activation

Unplanned security updates for Windows can now be downloaded:

Via Windows 10 Update History