Classification

Category: Malware

Type: Virus

Platform: W97M

Aliases: Chack

Summary


W97M/Chack is a rather simple Microsoft Word 97 macro virus.

Removal


Automatic action

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

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About the product

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Technical Details



Variant:Chack.A

When an infected document is opened the virus gets control. It will then disable the built-in macro virus protection and modify the customizations of Word. It disables both ALT+F8 (Tools/Macros/Macro) and ALT+F11 (Tools/Macros/Visual Basic Editor) keyboard shortcuts, removes the entire Tools/Macros submenu and disables the Visual Basic toolbar.

Then it will infect the global template. After that the virus will infect every document that is opened, created, or saved. Additionally it will hook Tools/Customize and Tools/Organizer menus.

The virus replaces the Help/About dialog with a dialog that contains a picture, a checkbox and two buttons. The same dialog will be shown in every Friday when user attempts to exit Word.

The virus code contains the following text:


 Macros By WinK'S Hacker
 Picture By Casper Satan
Lebih baik mencoba dari pada tidak tahu sama sekali ...
 Mohon ma'af bila telah mengganggu Anda.
 Microsoft memang gila ! Nambahin fasilitas pemrogramannya
 keterlaluan untuk suatu word prosesor.
 jangan harap kau datang lagi padaku

Variant:Chack.C

W97M/Chack.C is similar to W97M/Chack.A. The only difference is that it does not hook "Tools/Macros/Macro" menu.


Variant:Chack.H

This variant is almost identical with W97M/Chack.A. It will not hook the "File/Save" menu selection, and the last line of the text in the virus code is missing.


Variant:Chack.AI

W97M/Chack.AI is a slightly modified variant that does not hook "File/Save" or "Tools/Macros/Macro".