https://www.bleepingcomputer.com/news/security/microsoft-pushes-emergency-fix-for-windows-printnightmare-vulnerability/

Microsoft has released the KB5004945 emergency security update to fix the actively exploited PrintNightmare zero-day vulnerability in the Windows Print Spooler service impacting all Windows versions. However, the patch is incomplete and the vulnerability can still be locally exploited to gain SYSTEM privileges.

The remote code execution bug (tracked as CVE-2021-34527) allows attackers to take over affected servers via remote code execution (RCE) with SYSTEM privileges, as it will enable them to install programs, view, change, or delete data, and create new accounts with full user rights.