MYSQL Directory Write Test

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

class MetasploitModule < Msf::Auxiliary
  include Msf::Exploit::Remote::MYSQL
  include Msf::Auxiliary::Report
  include Msf::Auxiliary::Scanner
  include Msf::OptionalSession::MySQL

  def initialize
    super(
      'Name'           => 'MYSQL Directory Write Test',
      'Description'    => %Q{
          Enumerate writeable directories using the MySQL SELECT INTO DUMPFILE feature, for more
        information see the URL in the references. ***Note: For every writable directory found,
        a file with the specified FILE_NAME containing the text test will be written to the directory.***
      },
      'Author'         => [ 'AverageSecurityGuy <stephen[at]averagesecurityguy.info>' ],
      'References'  => [
        [ 'URL', 'https://dev.mysql.com/doc/refman/5.7/en/select-into.html' ]
      ],
      'License'        => MSF_LICENSE
    )

    register_options([
      OptPath.new('DIR_LIST', [ true, "List of directories to test", '' ]),
      OptString.new('FILE_NAME', [ true, "Name of file to write", Rex::Text.rand_text_alpha(8) ]),
      OptString.new('USERNAME', [ true, 'The username to authenticate as', "root" ])
    ])

  end

  # This function does not handle any errors, if you use this
  # make sure you handle the errors yourself
  def mysql_query_no_handle(sql)
    res = self.mysql_conn.query(sql)
    res
  end

  def run_host(ip)
    print_warning("For every writable directory found, a file called #{datastore['FILE_NAME']} with the text test will be written to the directory.")
    print_status("Login...") unless session

    # If we have a session make use of it
    if session
      print_status("Using existing session #{session.sid}")
      self.mysql_conn = session.client
    else
      # otherwise fallback to attempting to login
      return unless mysql_login_datastore
    end

    File.read(datastore['DIR_LIST']).each_line do |dir|
      check_dir(dir.chomp)
    end

  end

  def check_dir(dir)
    begin
      print_status("Checking #{dir}...")
      res = mysql_query_no_handle("SELECT _utf8'test' INTO DUMPFILE '#{dir}/" + datastore['FILE_NAME'] + "'")
    rescue ::Rex::Proto::MySQL::Client::ServerError => e
      print_warning(e.to_s)
    rescue Rex::ConnectionTimeout => e
      print_error("Timeout: #{e.message}")
    else
      print_good("#{dir} is writeable")
      report_note(
        :host  => mysql_conn.peerhost,
        :type  => "filesystem.file",
        :data  => "#{dir} is writeable",
        :port  => mysql_conn.peerport,
        :proto => 'tcp',
        :update => :unique_data
      )
    end
  end
end