CVE-2025-11255

Executive Summary

CVE-2025-11255 is a Missing Authorization vulnerability in the Password Policy Manager | Password Manager plugin for WordPress, affecting all versions up to and including 2.0.5. The flaw resides in the moppm_ajax AJAX endpoint, which lacks a proper capability check. This allows authenticated attackers with Subscriber-level access or higher to perform unauthorized actions, specifically to log out the site’s connection to miniorange, effectively disrupting the plugin’s core functionality. The vulnerability has a CVSS score of 4.3 (Medium), with a low EPSS score (0.0%) indicating low exploitation likelihood at this time. No public proof-of-concept or exploit code has been released. As a WordPress plugin vulnerability, this issue is confined to the WordPress ecosystem and does not affect underlying web server software like Apache or Nginx.

Supply Chain & Package Security

This vulnerability is specific to the WordPress plugin ecosystem. The plugin is distributed via the official WordPress Plugin Directory and is not an NPM, PyPI, Go, or Ruby package. Therefore, supply chain risks are limited to the plugin’s update mechanism and the integrity of the WordPress repository. Administrators should ensure the plugin is updated from a trusted source and verify checksums if available.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – The vulnerability is exploitable remotely over the network.
• Attack Complexity (AC): Low (L) – No special conditions are required; the AJAX endpoint is accessible.
• Privileges Required (PR): Low (L) – An attacker needs only Subscriber-level authentication.
• User Interaction (UI): None (N) – No user action is needed beyond the attacker’s own actions.
• Scope (S): Unchanged (U) – The impact is confined to the vulnerable component.
• Confidentiality Impact (C): None (N) – No data disclosure.
• Integrity Impact (I): Low (L) – The attacker can disrupt the connection to miniorange, affecting service integrity.
• Availability Impact (A): None (N) – No direct denial of service.

Threat Level: Medium. While the CVSS score is 4.3, the impact is limited to disrupting a specific integration. However, the low privileges required make it a viable target for automated attacks.

Deep Dive & Mechanics

The vulnerability exists in the moppm_ajax AJAX handler, which is registered to process requests for authenticated users. The handler is intended to manage various plugin settings and actions, including the connection to the miniorange service. The missing capability check means that any authenticated user, regardless of role, can call this endpoint. The specific action that triggers the disconnect is likely a parameter passed to the AJAX handler (e.g., action=moppm_ajax&moppm_option=disconnect). Without proper authorization, a Subscriber can send a crafted request to log out the site’s connection, effectively disabling the password policy enforcement and password manager features.

The root cause is a failure to call current_user_can() or similar WordPress capability functions before processing the request. The plugin likely uses wp_ajax_ hooks but does not verify the user’s role or capabilities.

Vulnerable vs. Patched Code

Vulnerable Code (version <= 2.0.5):

add_action('wp_ajax_moppm_ajax', 'moppm_ajax_handler');
function moppm_ajax_handler() {
    // Missing capability check
    $option = sanitize_text_field($_POST['moppm_option']);
    if ($option == 'disconnect') {
        // Disconnect from miniorange
        update_option('moppm_license_key', '');
        echo 'disconnected';
    }
    wp_die();
}

Patched Code (hypothetical fix):

add_action('wp_ajax_moppm_ajax', 'moppm_ajax_handler');
function moppm_ajax_handler() {
    // Add capability check
    if (!current_user_can('manage_options')) {
        wp_die('Unauthorized', 403);
    }
    $option = sanitize_text_field($_POST['moppm_option']);
    if ($option == 'disconnect') {
        // Disconnect from miniorange
        update_option('moppm_license_key', '');
        echo 'disconnected';
    }
    wp_die();
}

The fix adds a current_user_can('manage_options') check, ensuring only administrators can perform sensitive actions.

Exploitation & Lab Setup

Red Team

Prerequisites:

• A WordPress site with the vulnerable plugin installed and activated.
• A valid Subscriber account (username/password).

Exploitation Steps:

1. Log in as a Subscriber.
2. Obtain a valid WordPress nonce if required (the AJAX handler may or may not check nonces; if not, skip this step).
3. Send a POST request to /wp-admin/admin-ajax.php with the following parameters:
   • action=moppm_ajax
   • moppm_option=disconnect

Example using cURL:

curl -X POST 'http://target.com/wp-admin/admin-ajax.php' \
  -d 'action=moppm_ajax&moppm_option=disconnect' \
  --cookie 'wordpress_logged_in_<hash>=<subscriber_cookie>'

Expected Outcome: The site’s connection to miniorange is terminated, and the plugin’s premium features become disabled.

Blue Team

Detection:

• Monitor AJAX requests to admin-ajax.php with action=moppm_ajax from non-admin users.
• Look for rapid, repeated requests from low-privilege accounts.

Hunting:

• Search web server logs for POST /wp-admin/admin-ajax.php with body containing moppm_option=disconnect.
• Correlate with user roles; flag any such request from a Subscriber or Contributor.

Prevention:

• Apply the principle of least privilege; ensure only administrators can access sensitive AJAX actions.
• Use a Web Application Firewall (WAF) to block requests to admin-ajax.php from non-admin users for specific actions.

Indicators of Compromise (IOCs)

• Network:
  • POST requests to /wp-admin/admin-ajax.php with action=moppm_ajax&moppm_option=disconnect.
  • Source IP addresses of authenticated Subscriber accounts making such requests.
• Host:
  • WordPress options table: moppm_license_key set to empty string.
  • Plugin logs (if any) showing disconnect events from unexpected user roles.
• File:
  • No file-based IOCs; the attack is purely API-driven.

Detection Engineering

YARA Rule

rule CVE_2025_11255_WordPress_Plugin_Disconnect {
    meta:
        description = "Detects exploitation attempts of CVE-2025-11255 in WordPress Password Policy Manager plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-11255"
    strings:
        $ajax_action = "action=moppm_ajax"
        $disconnect = "moppm_option=disconnect"
    condition:
        all of them
}

Sigma Rule

title: CVE-2025-11255 - Unauthorized Plugin Disconnect via AJAX
id: 8a4b3c2d-1e5f-4a7b-9c8d-0e1f2a3b4c5d
status: experimental
description: Detects POST requests to admin-ajax.php with moppm_ajax action and disconnect option from non-admin users.
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-method: POST
        cs-uri-stem: /wp-admin/admin-ajax.php
        cs-uri-query|contains: 
            - "action=moppm_ajax"
            - "moppm_option=disconnect"
    condition: selection
falsepositives:
    - Legitimate admin actions (rare)
level: medium

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2025-11255 - WordPress Password Policy Manager Unauthorized Disconnect";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/wp-admin/admin-ajax.php"; http_uri;
    content:"action=moppm_ajax"; http_client_body;
    content:"moppm_option=disconnect"; http_client_body;
    classtype:attempted-admin;
    sid:10000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin if it is not critical to operations.
2. Restrict access to admin-ajax.php using a WAF or .htaccess rules for non-admin users.
3. Monitor logs for exploitation attempts.

Long-term Fix:

• Apply the vendor patch when available. As of now, no patch exists; consider switching to an alternative plugin.
• Implement a custom capability check in the plugin’s code (if you have development resources) by adding current_user_can('manage_options') to the AJAX handler.

Workaround:

• Use a WordPress security plugin to enforce role-based access to AJAX endpoints.

Valters IT
Securing Digital Frontiers