Google is hosting dozens of extensions in its Chrome Web Store that perform suspicious actions on the more than 4 million devices that have installed them and that their developers have taken pains to carefully conceal. The extensions, which so far number at least 35, use the same code …

As many of us celebrated the year-end holidays, a small group of researchers worked overtime tracking a startling discovery: At least 33 browser extensions hosted in Google’s Chrome Web Store, some for as long as 18 months, were surreptitiously siphoning sensitive data from roughly 2.6 million devices …