Threat description


Category: Malware
Type: Worm
Platform: W32


This worm is able of spreading through e-mail sending messages with different content. It has, as well, capability to spread through Kazaa's P2P network.


Automatic action

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

More scanning & removal options

More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.

You may also refer to the Knowledge Base on the F-Secure Community site for more information.

Contact Support

F-Secure customers can request support online via the Request support or the Chat forms on our Home - Global site.

Technical Details

The worm has three components, it was written in Visual Basic and packed with UPX. The first component if the one responsible for the installation into the system, it's an UPX file of length 9266 (24626 unpacked). The second component contains the main set of functionalities of the worm, the e-mail sending code. The third component is an UPX packed copy of the SMTP Control for Visual Basic. Which the worm will use to send the e-mail.

Installation to system

It will drop its components into the default temporary folder as:

explore.exe (main component)  a.exe (installation component)  smtp.ocx (SMTP Control for Visual Basic)   

All of the components will also be copied to the System32 windows folder. And will copy the installation component with the additional names:

a.bat  a.com  a.pif  a.scr   
P2P spreading

This worm will also read from the Windows registry the location of the Kazaa downloads folder and copy itself to that location.

Mass mailing

It will extract e-mail addresses from files in the users' computer which have one of the following extensions:

.htm  .html  .eml  .txt   

The messages sent by the worm will have the following characteristics:

Subjects are chosen from:

Check this out ;)",  )  Enjoy!  This is all i can send  Have Fun :)  You gonna love it  Here is what u wanted  ;)  Wait for more :)  looool  Take a look  Never mind !  Attatchments  See the attatched file", )  gift :)  Surprise!  save it for hard times  Happy Times :)  Useful  Very funny  Try it  you have to see this!  emazing!   

To which "Fw:" or "Re:" can be prepended.


Internet Explorer start page is set to:



Detection in F-Secure Anti-Virus was published on October 15th, 2003 in update: Detection Type:PC

Description Details: Ero Carrera, October 31st, 2003
Technical Details: Ero Carrera, October 31st, 2003


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