Zimuse leverages an IQ test to infect its victims.

An oddball hybrid malware program grabbed some electronic headlines this week. The bad app combines the activity of a worm with the infectious  properties of a virus. There appears to be two variants of it: Win32.Worm.Zimuse.A and Win32.Worm.Zimuse.B.

What makes the pernicious program queer is its destructive properties. These days, Black Hats tend to concentrate their efforts on programming schemes that have a cash payoff. When that’s your line of business, stealth, not havoc, is your modus operandi. Zimuse’s creators, through, don’t seem to care about monetary gain. Proliferation and mayhem appear to be their game.

Given the putative origin of the malware, it’s easy to understand why it departs from the malware mainstream. According to security experts, the black app was originally written to infect fans of a motorcycle club in the Liptov region of Slovakia. As can be the case with computer pranks, however, the malware started spreading wildly and soon began infecting corporate networks. Now badware watchers say the majority of the machines infected by the Zimuse variants are in the United States, followed by Slovakia, Thailand and Spain.

The malware is a two trick pony. First, it infects a machine and looks for ways to propagate itself. Then, after a defined number of days, it trashes its host’s Windows operating system and cripples it.

One way Zimuse distributes itself is by compromising legitimate Web sites. It’s planted as a self-unpacking zip file that contains an IQ test. When the IQ test installs itself on a machine, it also installs the malware. The IQ test is a legitimate application and serves to obfuscate what Zimuse is doing under the compromised computer’s hood.

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