Kaspersky Lab has found malware-laden Chrome extensions, along with a criminal gang playing cat and mouse with Google by releasing several variations of its wares.

The attacks manifest as suggestions to download Facebook apps. Those apps are, alas, not real. Instead they are malware and, in one case, a malware-laden Chrome extension hosted in Google's very own Chrome Web Store.

The malware pretends to be a Flash Player installer but instead downloads a Trojan which writes messages to a victim's Facebook profile and automatically Likes certain pages.

The former activity contains an alluring message suggesting your Friends download the same malware. The auto-Liking behaviour is part of a pay-per-Like scheme that helps the criminals to cash in.

Variations on this attack have been around for a few weeks now, Kaspersky says, but is so far largely confined to Brazil and other Portuguese-speaking nations.

Google is pulling the malware as fast as the criminals can sneak new variants into the Chrome Web Store.

Researcher Fabio Assolini suggests: “Be careful when using Facebook. And think twice before installing a Google Chrome extension.” ®