In 2006, as much as 25% of all cases processed by Trend Micro in its real-time case processing are related to file infectors. That is the second largest association of cases to a malware type, next only to Trojans’ 43%.

Considering that they are one of the earliest threat forms, the fact that file infectors are hitting it big is a major comeback.

In the outbreak era, worms reigned supreme. Now, in the age of targeted attacks, worms have given way to Trojan downloaders, spammers, and information stealers. So, when file infectors suddenly gain the capability to propagate or download malicious files, threat distinction goes out the window. PE_FUJACKS, a young family of file infectors discovered in the last quarter of 2006, is a testament to that.

FUJACKS propagate via multiple vectors, allowing for wide infection range and making it as dangerous as the has-been threat, worms. It also downloads files, which means it is just as potent as the new era’s leading malware, Trojan downloaders.

To read a comprehensive article detailing PE_FUJACKS’s routines and goals, click here: PE_FUJACKS: Jacking Up to the Times.