Virus.DOS.1260, also known as V2PX, is a memory-resident DOS virus that used a form of polymorphic encryption. This virus was written in 1989, but gone to wild in 1990. It was known as the first virus to use polymorphic encryption.


This virus infects any DOS executable file that is run in current directory and also those defined in the environmental variable PATH.

This virus is derived from Ralph Burger's Vienna virus source code, while this virus added a cipher and varies its signature by randomizing its decryption algorithm.