formatZero.c

#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>

#define SIZE 64

void vuln(char *string)
{
  if(strlen(string) < SIZE) {
    int target = 0;
    char buffer[SIZE];
    sprintf(buffer, string);
    if(target == 1330794330) {
       printf("You Win! :)\n");
       return;
    }
  }
  printf("Better Luck Next Time :P\n");
}

int main(int argc, char **argv)
{
  vuln(argv[1]);
}

32-bit : gcc -g formatZero.c -o formatZero_32 -m32 -fno-stack-protector
64-bit : gcc -g formatZero.c -o formatZero_64 -fno-stack-protector