Description

A widely distributed Chrome browser extension marketed as a “free” VPN service has been uncovered as a malicious tool designed to exploit users rather than protect them. Despite promoting privacy and secure browsing, the extension secretly operated as a traffic-redirecting proxy, ultimately compromising the online activity of more than 9 million users. Once installed, it hijacked web sessions, manipulated network routing, and silently captured data related to users’ browsing behavior. The scheme remained active for years, growing in scale as unsuspecting users continued installing the extension believing it offered legitimate VPN capabilities. The underlying motive behind the campaign was to create a large, distributed proxy network under attacker control. Instead of functioning like a real VPN, the extension injected remote PAC (Proxy Auto-Config) scripts, allowing its operators to redirect traffic through their own servers. This provided them the ability to observe browsing requests, collect hashed URL information, and even interfere with other security tools by disabling competing proxy-related extensions. The attackers also implemented persistence tactics such as keepalive scripts and browser history manipulation to remain undetected for as long as possible, ensuring continuous surveillance and sustained proxy access. To mitigate risks, users should immediately remove any suspicious or unknown VPN extensions and rely only on reputable, verified privacy tools. Reviewing browser permissions regularly and avoiding extensions that request extensive control over network settings can significantly reduce exposure. Organizations should implement strict browser extension policies, enforce security monitoring, and encourage periodic security audits on employee devices. Using endpoint protection and monitoring for unusual proxy configurations can further help detect similar threats early.