Security News > 2021 > July > Windows security update KB5004945 breaks printing on Zebra printers
Microsoft's recent out-of-band KB5004945 PrintNightmare security updates are preventing Windows users from printing to certain Zebra printers.
Windows 8.1 and Windows Server 2012 R2. Windows 7 SP1 and Windows Server 2008 R2 SP1. Windows Server 2008 SP2. However, researchers quickly determined that these patches did not fix the vulnerability in all cases.
In numerous reports shared on Twitter and Reddit [1, 2, 3, 4], Windows users state that they can no longer print to certain Zebra label printers after installing the update.
"We have about 1000 customers using Zebra printers and are getting flooded with calls from them not being able to print. This update is the culprit for sure as rolling it back has things spitting out again instantly," an affected person posted to the Sysadmin subreddit.
According to users affected by the bug, it is only affecting printers directly attached to Windows devices via USB. Zebra printers hooked up to a print server are not affected.
We are aware of a printing issue caused by the July 6 Windows "KB5004945" update affecting multiple brands of printers.