CVE-2023-47764

Executive Summary

CVE-2023-47764 is a Missing Authorization vulnerability in the WordPress plugin Ditty (ditty-news-ticker), affecting versions from n/a through 3.1.24. This flaw allows an unauthenticated attacker to exploit incorrectly configured access control security levels, potentially leading to unauthorized data access or modification. The vulnerability is classified under CWE-862 (Missing Authorization) and has a CVSS score of 6.5 (Medium). No public proof-of-concept (PoC) or exploit code has been identified at this time, and the patch status remains unknown. The EPSS score is 0.0%, indicating a low probability of exploitation in the wild currently, but the risk remains due to the lack of a vendor patch.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository. Users are advised to monitor the plugin's page for updates and apply patches immediately when available. Since the patch status is unknown, consider disabling the plugin or implementing virtual patching via a Web Application Firewall (WAF) until a fix is released.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
• Base Score: 6.5 (Medium)
• Attack Vector: Network (AV:N) – Exploitable remotely.
• Attack Complexity: Low (AC:L) – No special conditions required.
• Privileges Required: None (PR:N) – No authentication needed.
• User Interaction: None (UI:N) – No user action required.
• Scope: Unchanged (S:U) – Impact confined to the vulnerable component.
• Confidentiality Impact: Low (C:L) – Limited data exposure.
• Integrity Impact: Low (I:L) – Limited data modification.
• Availability Impact: None (A:N) – No denial of service.

Threat Level: Medium. The vulnerability is easy to exploit remotely without authentication, but the impact is limited to low confidentiality and integrity loss. The lack of a patch and public exploit increases the risk for unpatched installations.

Deep Dive & Mechanics

The vulnerability resides in the Ditty WordPress plugin, specifically in its access control mechanisms. The plugin fails to properly validate user permissions when processing certain AJAX requests or REST API endpoints, allowing unauthenticated users to perform actions that should require administrative privileges. This is a classic Missing Authorization flaw (CWE-862).

Root Cause: The plugin does not enforce capability checks (e.g., current_user_can('manage_options')) on critical functions, leaving them accessible to any visitor. Attackers can craft HTTP requests to manipulate plugin settings, ticker content, or other sensitive data.

Attack Vector: An attacker sends a crafted HTTP request to a vulnerable endpoint (e.g., /wp-admin/admin-ajax.php?action=ditty_save_settings) without any authentication token. The server processes the request due to missing authorization checks.

Impact: Successful exploitation could allow an attacker to:

• Modify ticker content (e.g., inject malicious scripts).
• Change plugin configuration (e.g., enable/disable features).
• Access sensitive data stored by the plugin.

Vulnerable vs. Patched Code

Since no patch is available, we can only analyze the vulnerable code pattern. The vulnerable version likely contains code similar to:

// Vulnerable: No capability check
add_action('wp_ajax_nopriv_ditty_save_settings', 'ditty_save_settings_callback');
function ditty_save_settings_callback() {
    // Process and save settings without checking user permissions
    update_option('ditty_settings', $_POST['settings']);
    wp_die();
}

A patched version would include an authorization check:

// Patched: Added capability check
add_action('wp_ajax_ditty_save_settings', 'ditty_save_settings_callback');
function ditty_save_settings_callback() {
    if (!current_user_can('manage_options')) {
        wp_die('Unauthorized', 403);
    }
    // Process and save settings
    update_option('ditty_settings', $_POST['settings']);
    wp_die();
}

Note: The nopriv prefix in the vulnerable code allows unauthenticated access, while the patched version removes it and adds a capability check.

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

1. Install WordPress (latest version) on a local server (e.g., XAMPP, Docker).
2. Install Ditty plugin version 3.1.24 (available from WordPress plugin archive).
3. Ensure the plugin is activated.

Exploitation Steps:

1. Identify vulnerable endpoints by analyzing the plugin's AJAX actions (e.g., using browser developer tools or source code review).
2. Craft a POST request to the vulnerable endpoint without authentication:

   curl -X POST http://target/wp-admin/admin-ajax.php \
        -d "action=ditty_save_settings&settings[malicious]=value"
   

3. Verify the change by checking the plugin's settings page or database.

Note: No public exploit code is available; this is a conceptual demonstration.

Blue Team (Defensive)

Detection:

• Monitor for unusual AJAX requests to admin-ajax.php with action parameters related to Ditty (e.g., ditty_*).
• Look for requests without a valid X-WP-Nonce header or WordPress authentication cookies.
• Check for unauthorized changes to the wp_options table (e.g., ditty_settings).

Mitigation:

• Disable the Ditty plugin until a patch is available.
• Implement a Web Application Firewall (WAF) rule to block requests to admin-ajax.php with action parameters starting with ditty_ from unauthenticated users.
• Use a security plugin (e.g., Wordfence) to enforce capability checks.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP POST requests to /wp-admin/admin-ajax.php with action=ditty_* parameters.
  • Requests lacking WordPress authentication cookies (wordpress_*, wordpress_logged_in_*).
• File IOCs:
  • Modified plugin files (e.g., ditty-news-ticker/ditty-news-ticker.php) with unauthorized changes.
• Database IOCs:
  • Unauthorized entries in wp_options table under ditty_settings or similar keys.
• Log IOCs:
  • WordPress debug log entries showing failed capability checks or unexpected AJAX calls.

Detection Engineering

YARA Rule

rule Detect_Ditty_Missing_Auth_CVE_2023_47764 {
    meta:
        description = "Detects vulnerable Ditty plugin files with missing authorization"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2023-47764"
    strings:
        $vuln1 = "add_action('wp_ajax_nopriv_ditty_" ascii wide
        $vuln2 = "add_action('wp_ajax_nopriv_ditty" ascii wide
        $vuln3 = "current_user_can" ascii wide
    condition:
        ($vuln1 or $vuln2) and not $vuln3
}

Sigma Rule

title: Detect Ditty Plugin Missing Authorization Exploitation
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects unauthorized AJAX requests targeting Ditty plugin endpoints
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'admin-ajax.php'
        cs-uri-query|contains: 'action=ditty_'
        sc-status: 200
    filter:
        cs-uri-query|contains: 'action=ditty_save_settings'  # Example, adjust as needed
    condition: selection and not filter
falsepositives:
    - Legitimate admin actions (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2023-47764 Ditty Plugin Missing Authorization Attempt"; flow:to_server,established; content:"POST"; http_method; content:"admin-ajax.php"; http_uri; content:"action=ditty_"; http_client_body; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the Ditty plugin if not essential for business operations.
2. Apply virtual patching via WAF to block unauthenticated requests to admin-ajax.php with action=ditty_* parameters.
3. Monitor logs for exploitation attempts (see IOCs and Detection Engineering).

Long-term Fix:

• Wait for the vendor (Metaphorcreations) to release a patched version. Check the WordPress plugin repository for updates.
• If no patch is forthcoming, consider replacing the plugin with an alternative that has active support.

Workaround:

• Manually add capability checks to the plugin's code (if you have development resources):

  // Add this line at the beginning of each vulnerable callback function
  if (!current_user_can('manage_options')) {
      wp_die('Unauthorized', 403);
  }
  

Valters IT
Securing Digital Frontiers