Researchers unearth a new and highly prolific malware framework used by its creators to generate over one billion fraudulent ad impressions over a time span of just three months. The attackers used the framework as part of three different ad fraud techniques for boosting their Google AdSense revenue with the help of a malicious browser extension which would produce AdSense impressions out of thin air, while also stealthily watching Twitch streams and generating fake YouTube likes in the background. The malicious activity surrounding this fraudulent AdSense campaign is focused on a handful of countries, with Russia, Ukraine, and Kazakhstan being the most prominent examples.
Source: https://www.bleepingcomputer.com/news/security/malicious-browser-extensions-used-by-hackers-for-ad-fraud/