The Zhelatin worm is a fairly serious plague on the Internet right now, you may have seen it recently in its most pervasive form, an email offering a “free greeting card”. (It’s often loosely referred to as the “storm worm”, since it’s an evolution of the worm that occurred earlier this year, which spammed users with the malware attached as a file, to emails about a storm in Europe. Now, instead of an attachment, it simply tries to get users to a website through spammed emails. The website attempts to install the malware through exploits.)
The latest tactic tries to trick the user into believing they’re downloading a YouTube video. F-Secure has a write-up here. They also have a good video here.