The ICEBRG Security Research team discovered four malicious Google Chrome extensions during a routine investigation of anomalous traffic. More than 500,000 users, including workstations in major businesses around the world, have been affected.
The team was analyzing an unusual spike in outbound traffic from a workstation at a European VPS provider. Upon further investigation of the traffic, researchers found four malicious extensions available in Google's Chrome Web Store: Change HTTP Request Header, Nyoogle - Custom Logo for Google, Lite Bookmarks, and Stickies - Chrome's Post-it Notes.
This finding highlights the threat of browser extensions, which are available in most major web browsers and an oft-overlooked attack vector. Threat actors know employees usually trust, and have control over, downloading these extensions. Using this knowledge, they can execute code via seemingly legitimate applications to gain a foothold into organizations.
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