Category: Malware

Type: Worm

Aliases: Kelvir, IM-Worm.Kelvir.A


Kelvir is an IM (Instant Messenger) worm that spreads by sending a link to its file using MSN Messenger. The worm also tries to download and run a file from Internet.


To get rid of this worm it is enough to delete its file from a hard disk. The latest versions of F-Secure Anti-Virus can automatically disable (rename) the worm's infected file. If automatic disinfection fails, please select 'Delete' disinfection action for the worm's file when it is detected. Instructions are here:

Please restart a computer after disinfection.

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Technical Details




The worm's file is a PE executable about 49 kilobytes long. The file is packed with a file compressor. The worm is written in Visual Basic.

The worm's file usually arrives on a computer with the MSN instant message message that looks like that:

lol! see it! u'll like it

The message contains a link that points to the worm's file named 'omg.pif' located on the '' webserver. When this file is downloaded and run by a user, it infects a computer and continues its spreading cycle by sending instant messages to all found MSN Messenger contacts.

Additionally the worm tries to download the following file:

This file is saved to the root of C:\ drive as 'dumprep.exe' and is then executed. The downloaded file is a variant of RBot backdoor and it is detected as ''. At the moment of the creation of this description the 'me.jpg' file was not accessible any longer.