F-Secure Virus Descriptions : Jerk

NAME:

Jerk

O97M/Jerk is a polymorphic macro virus that is able to infect both Excel and Word files. It gets control when an infected document is closed or an infected workbook is deactivated.

When it gets control, it attempts to infect all open workbooks in Excel as well as the Word's global template. After that it infects every Word document that is closed.

The virus activates its payload every 14th day of each month from June to December when user closes an infected document in Word. It displays a message with the title:

        Class.Poppy

with the text:

        I think (UserName) is a big stupid jerk!

where "(UserName)" is the current user name.

VARIANT: Jerk.B

This variant is functionally identical with O97M/Jerk.A, only the message is different. The title is:

        www.all.net

and the text is:

        V guvax (UserName) vf n ovt fghcvq wrex!

where "(UserName)" is the current user name.

[Analysis: Sami Rautiainen, F-Secure]