Extension Poisoning Campaign Highlights Gaps in Browser Security

A Christmas Eve phishing attack resulted in an unknown party taking over a Cyberhaven employee's Google Chrome Web Store account and publishing a malicious version of Cyberhaven's Chrome extension. While the problematic extension was removed within an hour of its discovery, the malicious activity highlights gaps in browser security that exist at most organizations and the necessity of getting a handle on the problem now, as extension poisoning is expected to be a persistent issue. Further research into the incident suggests that this attack was likely part of two separate, but potentially related, campaigns to target multiple extension developers to distribute malicious extensions, experts say. The campaigns may have begun as early as April 2023. "Currently we know about two different campaigns that have been targeting different objectives," says Amit Assaraf, CEO of Extension Total, a third-party extension security platform provider. Extension Total researchers have uncovered several malicious extensions over the past several weeks and have been looking at how they relate to each other. One campaign created extensions that steal cookies, session tokens, and possibly passwords, and targeted Facebook and OpenAI accounts, Assaraf says. The campaign relied on phishing to target extension developers and a malicious OAUTH application to take over Google Chrome Web Store accounts. Cyberhaven was one of the victims of this campaign. There is some disagreement among experts over when...