Masalah

Assemble your way to the flag (50pts)

My friend was trying out assembly for the first time, he has no clue what he's doing, help him out and procure your reward in the form of a flag :)

question  21403c32f66255742df510d2c44f527c

Penyelesaian

Buka binary question dengan IDA, dan ambil bilangan 2-3 digit, kemudian lakukan konversi ke ASCII.

import re
import sys

s = """int __cdecl main(int argc, const char **argv, const char **envp)
{
  printf(
    "Look for something else....\n",
    argv,
    envp,
    112LL,
    99LL,
    116LL,
    102LL,
    123LL,
    108LL,
    51LL,
    103LL,
    101LL,
    78LL,
    100LL,
    115LL,
    95LL,
    99LL,
    48LL,
    100LL,
    51LL,
    95LL,
    49LL,
    110LL,
    95LL,
    52LL,
    83LL,
    115LL,
    51LL,
    109LL,
    98LL,
    49LL,
    121LL,
}
    125LL);
  return 0;"""

# get 2,3 digits
for x in re.findall(r'\D(\d{2,3})\D', s):
    sys.stdout.write(chr(int(x)))