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#
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# Simple script to test a group of encoders against every exploit in the framework,
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# specifically for the exploits badchars, to see if a payload can be encoded. We ignore
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# the target arch/platform of the exploit as we just want to pull out real world bad chars.
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#
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msfbase = __FILE__
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while File.symlink?(msfbase)
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  msfbase = File.expand_path(File.readlink(msfbase), File.dirname(msfbase))
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end
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$:.unshift(File.expand_path(File.join(File.dirname(msfbase), '..', '..', 'lib')))
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require 'msfenv'
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$msf = Msf::Simple::Framework.create
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EXPLOITS = $msf.exploits
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def print_line(message)
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  $stdout.puts(message)
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end
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def format_badchars(badchars)
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  str = ''
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  if (badchars)
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    badchars.each_byte do |b|
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      str << "\\x%02X" % [ b ]
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    end
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  end
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  str
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end
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def encoder_v_payload(encoder_name, payload, verbose = false)
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  success = 0
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  fail = 0
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  EXPLOITS.each_module do |name, mod|
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    exploit = mod.new
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    print_line("\n#{encoder_name} v #{name} (#{format_badchars(exploit.payload_badchars)})") if verbose
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    begin
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      encoder = $msf.encoders.create(encoder_name)
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      raw = encoder.encode(payload, exploit.payload_badchars, nil, nil)
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      success += 1
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    rescue
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      print_line("    FAILED! badchars=#{format_badchars(exploit.payload_badchars)}\n") if verbose
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      fail += 1
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    end
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  end
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  return [ success, fail ]
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end
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def generate_payload(name)
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  payload = $msf.payloads.create(name)
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  # set options for a reverse_tcp payload
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  payload.datastore['LHOST'] = '192.168.2.1'
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  payload.datastore['RHOST'] = '192.168.2.254'
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  payload.datastore['RPORT'] = '5432'
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  payload.datastore['LPORT'] = '4444'
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  # set options for an exec payload
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  payload.datastore['CMD'] = 'calc'
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  # set generic options
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  payload.datastore['EXITFUNC'] = 'thread'
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  return payload.generate
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end
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def run(encoders, payload_name, verbose = false)
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  payload = generate_payload(payload_name)
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  table = Rex::Text::Table.new(
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    'Header' => 'Encoder v Payload Test - ' + ::Time.new.strftime("%d-%b-%Y %H:%M:%S"),
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    'Indent' => 4,
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    'Columns' => [ 'Encoder Name', 'Success', 'Fail' ]
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  )
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  encoders.each do |encoder_name|
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    success, fail = encoder_v_payload(encoder_name, payload, verbose)
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    table << [ encoder_name, success, fail ]
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  end
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  return table
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end
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if ($0 == __FILE__)
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  print_line("[+] Starting.\n")
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  encoders = [
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    'x86/bloxor',
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    'x86/shikata_ga_nai',
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    'x86/jmp_call_additive',
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    'x86/fnstenv_mov',
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    'x86/countdown',
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    'x86/call4_dword_xor'
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  ]
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  payload_name = 'windows/shell/reverse_tcp'
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  verbose = false
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  result_table = run(encoders, payload_name, verbose)
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  print_line("\n\n#{result_table.to_s}\n\n")
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  print_line("[+] Finished.\n")
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end
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