CVE-2024-51660

Executive Summary

CVE-2024-51660 is a Missing Authorization vulnerability in the Easy Accordion Gutenberg Block WordPress plugin by Binsaifullah, affecting versions up to and including 1.2.3. This flaw allows unauthenticated attackers to exploit incorrectly configured access control security levels, potentially leading to unauthorized data exposure or manipulation of accordion block settings. The vulnerability resides in the plugin's REST API or AJAX handlers, which fail to properly verify user capabilities before processing requests. With a CVSS score of 4.3 (Medium), the risk is elevated due to the lack of authentication requirements and the widespread use of Gutenberg blocks in WordPress ecosystems. No public exploit code or proof-of-concept is currently available, but the vulnerability is trivially exploitable by sending crafted HTTP requests to the vulnerable endpoints.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress Plugin Directory. Users who installed the plugin from the directory are at risk. The plugin is not available on NPM, PyPI, Go, or Ruby registries. Supply chain risk is moderate due to the lack of a patch and the plugin's reliance on WordPress core's permission model.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – Vulnerability does not affect other components.
• Confidentiality (C): Low (L) – Limited data exposure possible.
• Integrity (I): None (N) – No data modification.
• Availability (A): None (N) – No denial of service.

Threat Level: Medium. The vulnerability is easy to exploit but only allows limited information disclosure. However, in a WordPress context, this could expose sensitive configuration data or allow enumeration of user capabilities.

Deep Dive & Mechanics

The Easy Accordion Gutenberg Block plugin registers custom REST API endpoints or AJAX actions to handle accordion block operations (e.g., saving, loading, or updating block settings). The vulnerability stems from missing capability checks in these handlers. Specifically, the plugin fails to call current_user_can() or similar WordPress authorization functions before executing privileged actions.

Root Cause: The plugin's code likely uses wp_ajax_* hooks without verifying the user's role or capability. For example, a handler like wp_ajax_save_accordion_settings may be registered without checking if the user has edit_posts or manage_options capabilities. This allows any unauthenticated user to trigger the action.

Attack Vector: An attacker sends a crafted HTTP POST request to /wp-admin/admin-ajax.php with the appropriate action parameter. The server processes the request without authentication, potentially returning sensitive data or modifying plugin settings.

Impact: Unauthorized access to accordion block data, including potentially stored content or configuration. In worst-case scenarios, this could lead to privilege escalation if the plugin stores user roles or other sensitive metadata.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code pattern is as follows:

Vulnerable Code (PHP):

add_action('wp_ajax_save_accordion', 'save_accordion_callback');
add_action('wp_ajax_nopriv_save_accordion', 'save_accordion_callback');

function save_accordion_callback() {
    // No capability check
    $data = $_POST['accordion_data'];
    update_option('easy_accordion_data', $data);
    wp_die();
}

Patched Code (Hypothetical):

add_action('wp_ajax_save_accordion', 'save_accordion_callback');
// Remove nopriv hook to require authentication

function save_accordion_callback() {
    if (!current_user_can('edit_posts')) {
        wp_die('Unauthorized', 403);
    }
    $data = $_POST['accordion_data'];
    update_option('easy_accordion_data', $data);
    wp_die();
}

The patch adds a capability check using current_user_can('edit_posts') and removes the wp_ajax_nopriv_* hook to prevent unauthenticated access.

Exploitation & Lab Setup

Red Team

Prerequisites:

• Target WordPress site with Easy Accordion Gutenberg Block <= 1.2.3 installed and active.
• Network access to the target.

Exploitation Steps:

1. Identify the vulnerable AJAX action by analyzing the plugin's JavaScript or source code. Common actions include save_accordion, load_accordion, or update_accordion_settings.
2. Send a crafted request using curl:

curl -X POST http://target.com/wp-admin/admin-ajax.php \
  -d "action=save_accordion&accordion_data=test"

3. If the action returns data without authentication, the vulnerability is confirmed.

Proof-of-Concept (Python):

import requests

target = "http://target.com/wp-admin/admin-ajax.php"
data = {
    "action": "save_accordion",
    "accordion_data": "malicious_content"
}
response = requests.post(target, data=data)
print(response.text)

Blue Team

Detection:

• Monitor for unusual AJAX requests to /wp-admin/admin-ajax.php with unknown or suspicious action parameters.
• Look for requests lacking a valid WordPress nonce or session cookie.

Hunting Query (Splunk):

index=web sourcetype=access_combined
uri="/wp-admin/admin-ajax.php"
| search action=save_accordion OR action=load_accordion
| stats count by src_ip, uri, user_agent

Lab Setup:

• Use a local WordPress installation with the vulnerable plugin.
• Install a security plugin like Wordfence to log AJAX requests.
• Simulate exploitation and observe logs.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP POST requests to /wp-admin/admin-ajax.php with parameters like action=save_accordion or action=load_accordion.
  • Requests without a valid X-WP-Nonce header or WordPress authentication cookies.

• File IOCs:

  • Modified wp_options table entries with key easy_accordion_data containing unexpected values.
  • Plugin file /wp-content/plugins/easy-accordion-block/easy-accordion-block.php with missing capability checks.

• Behavioral IOCs:

  • Unauthorized changes to accordion block content on the frontend.
  • Unexpected database queries related to the easy_accordion option.

Detection Engineering

YARA Rule

rule Detect_Easy_Accordion_Missing_Auth {
    meta:
        description = "Detects missing authorization in Easy Accordion Gutenberg Block plugin"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2024-51660"
    strings:
        $ajax_hook = /add_action\(['\"]wp_ajax_nopriv_.*['\"]/
        $no_cap_check = /function .*_callback\(\)\s*\{[^}]*?(?!current_user_can)/
    condition:
        $ajax_hook and $no_cap_check
}

Sigma Rule

title: Detect Exploitation of CVE-2024-51660
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects unauthenticated AJAX requests to vulnerable Easy Accordion endpoints
author: Valters IT
logsource:
    category: webserver
    product: apache
    service: access_combined
detection:
    selection:
        cs-uri-query|contains: "/wp-admin/admin-ajax.php"
        cs-uri-query|contains: "action=save_accordion"
    condition: selection
falsepositives:
    - Legitimate admin actions (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-51660 Easy Accordion Missing Auth"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=save_accordion"; http_client_body; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until a patch is available. Navigate to WordPress Admin > Plugins and deactivate "Easy Accordion Gutenberg Block".
2. Implement a Web Application Firewall (WAF) rule to block requests to /wp-admin/admin-ajax.php with suspicious action parameters.
3. Add custom code to your theme's functions.php to block unauthenticated AJAX requests:

add_action('init', function() {
    if (defined('DOING_AJAX') && DOING_AJAX && !is_user_logged_in()) {
        $blocked_actions = array('save_accordion', 'load_accordion');
        if (isset($_POST['action']) && in_array($_POST['action'], $blocked_actions)) {
            wp_die('Unauthorized', 403);
        }
    }
});

Long-term Fix:

• Contact the plugin vendor for an official patch.
• Monitor the WordPress Plugin Directory for updates.
• Consider replacing the plugin with an alternative that follows secure coding practices.

Valters IT – Securing digital ecosystems through proactive threat intelligence.