Classification

Category: Malware

Type: Virus

Aliases: Donut, .NET virus, Dotnet

Summary


Donut is the first known virus implemented in the Microsoft C# and Microsoft Intermediate Language (MSIL). It targets binary files under Microsoft .NET architecture.

Sample of this virus was posted by the virus author directly to several anti-virus companies on January 9th, 2002.

Removal


Automatic action

Based on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the detected program or file, or ask you for a desired action.

Knowledge Base

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About the product

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Submit a sample

Submit a file or URL for further analysis.

Technical Details


The virus itself is very simple and will never become a real-world problem.

The Donut virus is 8kB long. When executed, it infects all other .NET executables with .EXE extension in the current directory and directories above it.

After this, there's a one-in-ten chance the virus will show a dialog box with this text:

This cell has been infected by dotNET virus!
 .NET.dotNET by Benny/29A

The virus will then just exit. It doesn't stay in memory and will only spread further if an infected file is executed again.

The first fully .NET compliant operating system from Microsoft, known as 'Blackcomb', is estimated to ship in 2003.

Donut has not been found in the wild. It is not considered to pose any threat at the moment. Nevertheless, it's the first virus of its kind.