PrintNightmare Aftermath: Windows Print Spooler is Better. What’s Next?

While Microsoft has boosted the security of Windows Print Spooler in the three years since the disclosure of the PrintNightmare vulnerability, the service remains a spooky threat that organizations cannot afford to ignore.

The 2021 PrintNightmare vulnerability exposed multiple deep-rooted security flaws in Microsoft’s Print Spooler service, a core Windows component. The flaws, which had persisted in the Print Spooler for years, forced Microsoft to change the default behavior of the service, and organizations to change how they enabled printing services for users. While Microsoft’s changes have overall improved Print Spooler’s security, researchers caution the service still remains a prime target for attackers. The potential weaknesses resulting from Microsoft’s efforts to maintain backward compatibility with legacy code leaves Print Spooler vulnerable.