A new virus called Simile.D may not be much of a threat to computer systems, but some of its technical tricks could lead to a rethinking of the principles underlying antivirus software.
The program has code that not only works hard to hide the virus' presence, it also randomizes the program's size so as to make it harder to identify. On top of that, the fourth and latest variant of the bug--which emerged this week--can spread to both Windows and Linux computers.
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