One independent cybersecurity researcher said 'opportunistic effort' affected other extensions including artificial intelligence and virtual private network tools.

The attack began after a hacker successfully targeted a Cyberhaven employee via a phishing email that was sent to Chrome extension developers. The employee, believing the email was an official Google contact, clicked the email and input their login credentials on the phishing page.

Hackers have compromised several different companies' Chrome browser extensions in a series of intrusions dating back to mid-December, according to one of the victims and experts who have examined the campaign.