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How to Install the Microsoft Emergency PrintNightmare Vulnerability Patch

By Brian Burgess

Published July 7, 2021

Microsoft is releasing an emergency patch update to fix a critical print spooling bug to all users of Windows 10 and Server. Here’s why you need to install it now.

Microsoft is releasing a new critical vulnerability patch called “PrintNightmare.” It was revealed in July 2021, and the company is urging all users to download and install the critical patch now.

PrintNightmare Vulnerability Patch

This vulnerability is a critical flaw with the Windows Print Spooler service. It is similar to the Printing Patch that was released in June 2021.

Here is what the company notes about this latest out-of-band patch:

A remote code execution vulnerability exists when the Windows Print Spooler service improperly performs privileged file operations. An attacker who successfully exploited this vulnerability could run arbitrary code with SYSTEM privileges. An attacker could then install programs; view, change, or delete data, or create new accounts with full user rights.

UPDATE July 6, 2021: Microsoft has completed the investigation and has released security updates to address this vulnerability. Please see the Security Updates table for the applicable update for your system. We recommend that you install these updates immediately. If you are unable to install these updates, see the FAQ and Workaround sections in this CVE for information on how to help protect your system from this vulnerability. See also KB5005010: Restricting installation of new printer drivers after applying the July 6, 2021 updates.

Note that the security updates released on and after July 6, 2021, contain protections for CVE-2021-1675, and the additional remote code execution exploit in the Windows Print Spooler service known as “PrintNightmare”, documented in CVE-2021-34527.

Manually Update this Critical Vulnerability

You should see the patch come through in the background. Microsoft is releasing it quickly to  the following with more to follow soon:

Windows 10, Windows 8.1, Windows RT 8.1, Windows 7, and several versions of Windows Server, including 2019, 2012 R2, and 2008 releases. Updates for Windows Server 2012 and 2016 are coming soon, along with an update for Windows 10 version 1607.

To update head to Start > Settings > Update & Security and manually check for updates. Then note that a restart of your system is required to finish the installation and patching process. Just make sure to grab it when you know you’ll have some downtime while working.

If something breaks after you install today’s updates and cannot be resolved by Microsoft’s documented workarounds, you can roll them back.

For more on how to do that, makes sure to read our article: How to Uninstall a Windows 10 Cumulative Update.