Kelvir

Classification

Kelvir, IM-Worm.Kelvir.A

Summary

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.

Removal

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:

https://support.f-secure.com/enu/home/virusproblem/howtoclean/howtodeleteinfec...

Please restart a computer after disinfection.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

Check for the latest database updates
First check if your F-Secure security program is using the latest updates, then try scanning the file again.
Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note: You need administrative rights to change the settings.

Technical Details

Variant:IM-Worm.Kelvir.B

Variant:W32/Kelvir.B

Size:49011

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 'home.earthlink.net' 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:

http://home.earthlink.net/~gallery10/me.jpg

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 'Backdoor.Win32.Rbot.kp'. At the moment of the creation of this description the 'me.jpg' file was not accessible any longer.