The first virus capable of infecting systems running 64-bit versions of the Windows operating system has been discovered by researchers at Anti-Virus firm Symantec.
The virus, called "W64.Rugrat.3344" or Rugrat is believed by the company to be a "proof-of-concept" virus rather than one destined to be released into the wild. It also thinks the author responsible for the virus has also written at least six other virus "firsts". These are collected under the name W32.Chiton.gen.
The virus infects files that are in the same folder as the virus and in all subfolders. It is the first known virus for 64-bit Windows, and it uses the Thread Local Storage structures to execute the viral code. Symantec said this was "an unusual method of executing code". The threat has been rated "low" for the time being.
Worrying, the virus could also infect 32-bit machines running 64-bit emulation software, the company warned.