execl("/bin/sh", "sh", NULL);

-r--------  1 level8  level8    412 Apr 25  2015 level08.c
-r--------  1 level9  level9     13 Apr 25  2015 level08.pass

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

int main(int argc, char *argv[]) {
        char buf[64];
        FILE *fp;
    signal(SIGABRT, SIG_DFL);
    fp = fopen("/levels/level08.pass", "r");
        fgets(buf, 64, fp);
        buf[strcspn(buf, "n")] = '';
        if(strcmp(buf, argv[1]))
                raise(SIGABRT);
        execl("/bin/sh", "sh", NULL);
}