KB5005010 applies to Windows 10 2004 and above and Windows Server 2004 and above.
Security updates released on and after July 6, 2021 contain protections for a remote code execution exploit in the Windows Print Spooler service known as “PrintNightmare”, documented in CVE-2021-34527. After installing these and later Windows updates, non-administrators are only allowed to install signed print drivers to a print server. By default, administrators can install both signed and unsigned printer drivers to a print server. Signed drivers are trusted by the installed root certificates in the system’s Trusted Root Certification Authorities.
Prior to installing the July 6, 2021, and newer Windows Updates containing protections for CVE-2021-34527, the printer operators’ security group could install both signed and unsigned printer drivers on a printer server. After installing such updates, delegated admin groups like printer operators can only install signed printer drivers. Administrator credentials will be required to install unsigned printer drivers on a printer server going forward.
The print industry has been freaked out over the problems in the industry. Many use Windows machines to handle print tasks from clients which makes it frustrating.