Summary

The Zelu trojan is disguised as a 'ChipTec Y2K - Freeware Version' utility. When the trojan is run it scans all directories and corrupts all files it can open for writing.

Additional Details

The trojan puts the following messages in the beginning of corrupted files:

 @ This file is sick !
 @ It was contaminated by the radiation liberated
 @ by the explosion of the atomic bomb.

After the trojan finishes 'scanning' the files it outputs:

 @ Hello !
 @ My name is ZELU.
 @ I'm a virus.
 @ I detonated the atomic bomb in your hard disk.
 @ Good-bye !

 Press ENTER to continue . . .

After 'Enter' pressed the trojan passes control to operating system. In some cases an attacked computer is reset. By this time the operating system is not usable and has to be fully reinstalled. All data on the attacked system is lost.

If the trojan is just run, its task can be killed from Windows Task Manager. This will save most of data on a hard disk.

Here's a screenshot of the trojan:



[Analysis: Alexey Podrezov, F-Secure Corp.]