A vulnerability has recently been exposed in every version of Microsoft Windows which would allow an attacker to remotely execute code and escalate privilege to SYSTEM.
There was a separate vulnerability with the print spooler service recently discovered dubbed PrintNightmare and I can confirm that this vulnerability is a completely new hole in the print spooler service and is about as bad as it can get (as was the PrintNightmare vulnerability).
Both of these security vulnerabilities would allow an attacker complete control of your computer e.g installing software, modifying files and creating new administrator accounts!
Microsoft are yet to patch this latest vulnerability, but for now it is suggested to disable the print spooler service altogether.