The security firm confessed to the mistake in a blog post on Tuesday, and assured firms that the update has since been pulled.
"It saddens me to report that at around 3PM PST yesterday, Malwarebytes released a definitions update that disabled thousands of computers worldwide," wrote Malwarebytes Marcin Kleczynski.
"Within eight minutes, the update was pulled from our servers. Immediately thereafter, users flocked to our support helpdesk and forums to ask us for a fix."
The update definition made it so Malwarebytes protection software treated essential Windows .dll and .exe files as malware, stopping them from running and thus knocking IT systems and PCs offline.
The INQUIRER has heard from some IT managers that the update caused untold havoc on their systems.
Malwarebytes update accidentally deletes legitimate system files
Posted on Thursday, April 18 2013 @ 13:08 CEST by Thomas De MaesschalckThe Inquirer reports Malwarebytes rolled out a faulty update earlier this week that flagged legitimate system files as malware:
