Summary

W97M/Bablas is a Word 97 macro virus.

When an infected document is opened, the virus infects the global template. While infecting, the virus changes the Word application window title bar to:

    Bpp Hacker is now activating

and the active document window title bar to:

    (I Don't mean to disturb.)

After infection is done, the virus restores the texts of title bars back to normal. The same behaviour is visible, when "File/Open" dialog is opened in the infected Word.

When the global template is infected, the virus infectes all documents that are opened, closed or saved.

The payload activates in any Friday and Sunday every time the Word is closed only if the current time is less than 9:00 pm. Then the virus causes computer to beep and displays a message:

    Terimakasih buat dosenku yang amat sangat "bijaksana",
    yang telah memberiku nilai JELEK. Saya merasa bangga
    dan sungguh-sungguh bangga terhadap dosenku itu.
    Sekali lagi saya ucapkan terimakasih!.

    Semoga mereka tetap di STIKI.
    (buat teman-teman, ma'af mengganggu.)

[Analysis: Katrin Tocheva and Sami Rautiainen, F-Secure]