The “Dormant Colors” is yet another vast campaign of malicious extensions with millions of active installations worldwide, this time with a color-related theme and full of deception all through the chain. It starts with the trickery malvertising campaign, continues with a crafty novel way to side-load the real malicious code without anyone noticing (until now!), and finally with stealing not only your searches and browsing data, but also affiliation to 10,000 targeted sites — a capability that is easily leveraged for targeted spear phishing, account takeover and credential extraction — all using this powerful network of millions of infected computers worldwide!

A few months ago, we blogged about malicious extensions redirecting users to phishing sites and inserting affiliate IDs into cookies of eCommerce sites. Since that time, we have investigated several other malicious extensions and discovered 5 extensions with a total install base of over 1,400,000 "...the extensions also track the user’s browsing activity."