KB5027231Broken

Chrome broken for all Malwarebytes users

Google ChromeMalwarebytesWeb Browsing

What broke

June’s update changed Windows exploit protection in a way that made Malwarebytes’ anti-exploit module think Chrome was malicious. Chrome processes would run in the background, but the browser window never appeared. Given that Malwarebytes has millions of users and Chrome has about 65% browser market share, this was a significant number of people who suddenly couldn’t browse the web. Trying to uninstall the update via WSUS produced a “catastrophic error.” The world’s most popular browser, broken by the world’s most popular antivirus, caused by the world’s most popular operating system’s update.

Sources

  1. BleepingComputer: KB5027231 incident report
  2. Neowin: KB5027231 incident report