Lord of SQL injection – darkknight
Level 12
Source Code
<?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__); ?>
Analyse
http://los.sandbox.cash/darkknight-~~.php?pw=123&no=12
이라고 입력하게 되면
select id from prob_darkknight where id='guest' and pw='123' no=12
과 같이 MySQL 쿼리문이 입력된다.
그리고 5번째 줄에서 ‘or’, ‘and’, ‘substr’, ‘=’, ‘ascii’이 필터링 되어있다.
15번째 줄을 보면 &result['pw']
에 admin의 pw가 들어가야만 darkknight문제가 풀린다.
Frist Hint is next page