Last week, antivirus vendors exposed Donut, supposedly the world's first .Net virus. Only it isn't a. NET virus, Microsoft argues.

Donut is simply a native executable that elects to modify only applications written for the Microsoft .NET Framework in the Microsoft Intermediate Language (MSIL) PE format, the software firm says.

"In fact, the method of infection is the same as many much older viruses, and it is detected by anti-virus software as a much older loader virus," Microsoft states in an open letter on the subject.

Rob Rosenberger, editor of Vmyths.com, the definitive chronicler of the hype and hysteria which envelops computer security, supports Microsoft's assessment. Donut would be better termed an "executable wrapper" than a .NET virus, he says.

"If you can envelop a .ZIP file within a self-extractor .EXE module, then OF COURSE you can do the same with a .NET file.

"It appears the author relied heavily on assembler, plus some C code, plus a token amount of MSIL. The author went to some rather impressive lengths to envelop a .Net file within a non-.NET module."

Describing Donut as the first .NET virus was like "like using the term 'woman' to describe a male cross-dresser", Rosenberger argues.

Jack Clark, product marketing manager for the McAfee division of Network Associates, said since Donut affected only machines with .NET installed and not Win32 machines it was reasonable to describe it as a .NET virus.

He agreed with Microsoft's assessment of the low threat posed by Donut but maintained that its existence was "proof of concept" that .NET might be used maliciously. ®

External links

Description of the virus by McAfee

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