TechTweak.Co.cC

In this post I will show how to create a simple virus that disables/blocks the USB ports on the computer (PC). As usual I use my favorite C programming language to create this virus. Anyone with a basic knowledge of C language should be able to understand the working of this virus program.

Once this virus is executed it will immediately disable all the USB ports on the computer. As a result the you’ll will not be able to use your pen drive or any other USB peripheral on the computer. The source code for this virus is available for download. You can test this virus on your own computer without any worries since I have also given a program to re-enable all the USB ports.

1. Download the USB_Block.rar file on to your computer.

2. It contains the following 4 files.

block_usb.c (source code)
unblock_usb.c (source code)
3. You need to compile them before you can run it. A step-by-step procedure to compile C programs is given in my post - How to Compile C Programs.

3. Upon compilation of block_usb.c you get block_usb.exe which is a simple virus that will block (disable) all the USB ports on the computer upon execution (double click).

4. To test this virus, just run the block_usb.exe file and insert a USB pen drive (thumb drive). Now you can see that your pen drive will never get detected. To re-enable the USB ports just run the unblock_usb.exe (you need to compile unblock_usb.c) file. Now insert the pen drive and it should get detected.

5. You can also change the icon of this file to make it look like a legitimate program.(This step is also optional)

In many of my previous posts especially in the VIRUS CREATION section, I have used C as the programming language. If you’re new to C programming and find it difficult to compile the C source codes then this post is for you. Here is a step-by-step procedure to install Borland C++ compiler 5.5 and compile C programs.

How to install Borland C++ compiler
1. Download Borland C++ compiler 5.5 (for Windows platform) from the following link.

http://www.codegear.com/downloads/free/cppbuilder

2. After you download, run freecommandlinetools.exe. The default installation path would be

C:\Borland\BCC55

How to configure Borland C++ compiler
1. After you install Borland C++ compier, create two new Text Documents

2. Open the first New Text Document.txt file and add the following two lines into it

-I”c:\Borland\Bcc55\include”

-L”c:\Borland\Bcc55\lib”

Save changes and close the file. Now rename the file from New Text Document.txt to bcc32.cfg.

3. Open the second New Text Document (2).txt file and add the following line into it

-L”c:\Borland\Bcc55\lib”

Save changes and close the file. Now rename the file from New Text Document (2).txt to ilink32.cfg.

4. Now copy the two files bcc32.cfg and ilink32.cfg, navigate to C:\Borland\BCC55\Bin and paste them.

How to compile the C source code (.C files)
1. You need to place the .C (example.c) file to be compiled in the following location

C:\Borland\BCC55\Bin

2. Now goto command prompt (Start->Run->type cmd->Enter)

3. Make the following path as the present working directory (use CD command)

C:\Borland\BCC55\Bin

4. To compile the file (example.c) use the following command

bcc32 example.c

5. Now if there exists no error in the source code you’ll get an executable file (example.exe) in the same location (C:\Borland\BCC55\Bin).

6. Now you have successfully compiled the source code into an executable file(.exe file).

NOTE: The above tutorial assumes that you’ve installed the compiler onto the C: drive (by default).

Some times it becomes necessary to change the ICON of an executable(.exe) file so that the exe file get’s a new appearence.Many of the Tools such as TuneUP Winstyler does this job by adjusting the Windows to display a custom icon to the user.But in reality when the file is carried to a different computer, then it shows it’s original ICON itself.This means that inorder to permanantly change the ICON, it is necessary to modify the executable file and embed the ICON inside the file itself.Now when this is done the exe file’s ICON is changed permanantly so that even if you take file to a different computer it show’s a new icon.

For this purpose I have found a nice tool which modifies the exe file and will embed the ICON of your choice into the file itself. ie:The tool changes the exe ICON permanantly.

I’ll give you a step-by-step instruction on how to use this tool to change the icon.

1. Goto www.shelllabs.com and download the trial version of Icon Changer and install it (Works on both XP and Vista).

2. Right-click on the exe file whose ICON is to be changed.

3. Now you will see the option Change Icon…Click on that option.

4. Now the Icon Changer program will open up.

5. Icon changer will search for all the ICONS on your system so that you can select any one of those.

6. Now select the ICON of your choice and click on SET.

7. Now a popup window will appear and ask you to select from either of these two options.

[list=]Change embeded icon.
Adjust Windows to display custom icon.
Select the first option (Change embeded icon).
[/list]
8. You are done.The ICON get’s changed.