Antivirus used by millions mistakenly blocked all Google sites, causing chaos


Image: Luis Alvarez/Getty Images

A popular antivirus used by millions of people around the world on Wednesday blocked all Google sites and services due to an error.

For about an hour on Wednesday morning, some people who had Malwarebytes antivirus installed on their computers were unable to visit any Google sites or use services like Gmail or the Google Play Store, according to people complaining about the issue on Twitter. .

Naomi Clark, game designer and teacher at New York University’s Game Center, who wrote on Twitter about the issue, Motherboard told the websites “wouldn’t load, like they were blocked by a firewall.”

“But even before that, my Malwarebytes install started showing me system notifications that a malicious site was blocked, dozens per minute, all Google domains,” she said. “That’s how I understood what must have happened.”

clark said in a tweet that this issue “reminds you of how littered Google’s ad tracking IPs are with absolutely everything.”

Kyle Polley, who works in cybersecurity, said her fiancé was affected by the issue.

“She received what looked like an infinite number of alerts like ‘malwarebytes blocked’ of ” where is Chrome or Edge and was,,, etc. Any Google site or any site that uses Google in any way hasn’t worked,” he told Motherboard. “She had to disable Malwarebytes to do her job.”

Marcin Kleczynski, CEO and co-founder of Malwarebytes, told Motherboard that it was “an accidental false positive. Fixed pretty quickly”, and that it only affected Windows users.

“Unfortunately always a noisy event when you have millions of users,” Kleczynski added.

Malwarbytes first acknowledged the issue around 11:30 a.m. ET in a tweet.

“We are aware of a temporary issue with the web filtering component of our product which may block certain domains, including We are actively working on a fix and will update Twitter as soon as we have more information”, the company wrote on Twitter.

About an hour later, the company wrote that the issue was resolved and the update “should happen automatically.”

Kleczynski said the issue lasted about 30 minutes. Clark said it lingered for about an hour and a half for her. Several people responded to the company’s tweets saying the issue was resolved, complaining that it was still ongoing.

Google did not immediately respond to a request for comment.

UPDATE, 4:17 p.m. ET: This story has been updated to include additional information.

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