When Mark Washburn was working on an analysis of the Vienna and Cascade viruses with Ralf Burger, he developed the first family of polymorphic virus called the Chameleon family.
The 1260, or V2PX, was the first computer virus that used a form of polymorphic encryption. Washburn created the virus derived from Ralph Burger's publication of the disassembled Vienna virus source code. The 1260 added a cipher and varied its signature by randomizing its decryption algorithm. 1260 is a memory-resident DOS virus, like Vienna, affects
1260 was written in 1989, derived from Ralph Burger's Vienna virus source code, the 1260 added a cipher and varied its signature by randomizing its decryption algorithm. 1260 infects .COM files in the current or PATH directories upon execution. Changing an authenticated executable file is detected by most modern computer operating systems.
While its basic functions were based mostly on Vienna, the 1260 is original enough to be considered to have its own family.