Microsoft’s KB5004945 Security Update for PrintNightmare Has Side Effects: Now Zebra Printers Crash
Microsoft 6th July Updates Make Zebra Printers Stop Working. Users Need to Uninstall Them to Use the Printing Machines.
The security updates aimed at PrintNightmare make Zebra printers crash after installed. PrintNightmare is a zero-day bug classified as CVE-2021-34527, which has made quite a stir in the cybersecurity world lately, being mistakenly made public. After the suggested mitigation measures, Microsoft provided a security patch KB5004945 that goes with Windows 10 versions 2004, 20H1, and 21H1 to fight the zero-day.
Besides the fact that the out-of-band KB5004945 proved inefficient to remove PrintNightmare as per security researchers’ demonstration, now the update once installed, prevents people who use Zebra printers to print on some Zebra versions as they literally stop working when doing so.
What Happened and What Zebra Printers Are Affected?
Windows users have reported that after installing the KB5004945 Microsoft security patch, they cannot print anymore to some Zebra Printing Labels.
However, not all versions seem to be affected, the ones that do not work after installing the update are ZD620, ZT230, ZT410, LP 2844, ZT220, ZD410, ZD500, ZT420.
Users also revealed that Zebra printers that connect to a print server seem to work fine, so they are not affected by the update, only those directly connected through a USB to Microsoft devices stop being functional.
Why Zebra Printers Are Affected by This New Update?
The reason why Zebra printers do not match with the new Windows security updates for Printnightmare is not actually determined. But, as we also mentioned yesterday in our piece of news and a thing that was stopping also the 0patch free micropatch that really works against both RCE and LPE components of Printnightmare was that the Microsoft update, once installed, modifies the localspl.dll file. It might be that this change interferes with Zebra Printers too.
Zebra and Windows Aware of the Issue
Microsoft is aware of the issue:
After installing this update, you might have issues printing to certain printers. Most affected printers are receipt or label printers that connect via USB.
Zebra Printers Company also shared their input on the matter:
We are aware of a printing issue caused by the July 6 Windows “KB5004945“ update affecting multiple brands of printers. Microsoft has investigated this issue and plans to release an update addressing the issue within the next 1–2 business days. An immediate way to address the issue is to uninstall the Windows “KB5004945“ update or uninstall the affected printer driver and reinstall using Administrative credentials.
What’s the Solution Until Zebra Printers Issue Is Fixed?
The first solution would be to uninstall the Microsoft updates. To do so, you can just type Windows Update on the Search or Start Menu. Click on “View your update history” on the screen for Windows Updates. Go to “View Update”, then Uninstall Update. Once you reached the Control Panel, find the problematic security update that needs to be uninstalled and click on Uninstall.
Another way recommended by Windows is to run wusa /uninstall /kb:5004945 /promptrestart command in Command Prompt or Powershell.
Microsoft also recommends using the Known Issue Rollback. This will work for normal users, but enterprises should install and configure a Group Policy. Keep in mind that a restart is needed after any of these recommended updates, in order to make them start working.
Zebra Printers focus on label printers that are intended for industrial purposes and are known for their flexibility in customizing the label according to your own requirements in terms of label size, resolution, quality, and so on. Addressing this issue, Zebra has an available Support Team that can help you with printer issues caused by the latest Microsoft security updates.