This level moves on from format1 and shows how specific values can be written in memory.
This level is at /opt/protostar/bin/format2
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
int target;
void vuln()
{
char buffer[512];
fgets(buffer, sizeof(buffer), stdin);
printf(buffer);
if(target == 64) {
printf("you have modified the target :)\n");
} else {
printf("target is %d :(\n", target);
}
}
int main(int argc, char **argv)
{
vuln();
}