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.

The data-loss startup says it was targeted as part of a "wider campaign to target Chrome extension developers."

Hackers have compromised several popular Chrome extensions with hundreds of thousands of users, TechCrunch reported today. One of the affected extensions is developed by Cyberhaven Inc., a venture-backed cybersecurity provider. The company confirmed the incident in a statement.

Cyberhaven, a California-based cyber security firm says it was recently hacked on Christmas Eve, and that the hackers were targeting Chrome extensions. Cyberhaven doesn’t mention what the reasoning for the attack was,