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.

Cyberhaven, a California-based cyber security firm says it was recently hacked on Christmas Eve, and that the hackers were targeting Chrome extensions.

Other extensions possibly affected include Internxt VPN, VPNCity, Uvoice, and ParrotTalks, as Bleeping Computer writes. Cyberhaven says hackers pushed an update (version 24.10.4) of its Cyberhaven data loss prevention extension containing the malicious code on Christmas Eve at 8:32PM ET.

Browser extensions are typically used by internet users to customize their Web-browsing experiences, for example by automatically applying coupons to shopping websites.