CVE-2025-39560

Executive Summary

CVE-2025-39560 is a Missing Authorization vulnerability in the Live Forms WordPress plugin by Shahjada, affecting versions up to and including 4.8.4. This flaw allows an authenticated attacker (with low privileges) to exploit incorrectly configured access control security levels, potentially leading to unauthorized data access or modification of form submissions and settings. The vulnerability is classified under CWE-862 (Missing Authorization) and has a CVSS score of 5.4 (Medium). As of this report, no official patch is available, and no public exploit code or proof-of-concept has been released. The EPSS score is 0.0%, indicating a low probability of active exploitation in the wild, but the risk remains significant for unpatched installations.

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 update channel and apply any security patches immediately upon release. Since the plugin is part of the WordPress ecosystem, supply chain risks include compromised updates or malicious forks. Administrators should verify plugin integrity via checksums and restrict installation to trusted sources.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – The vulnerability can be exploited remotely.
• Attack Complexity (AC): Low (L) – No special conditions are required.
• Privileges Required (PR): Low (L) – An attacker needs a valid user account with low privileges.
• User Interaction (UI): None (N) – No user action is needed.
• Scope (S): Unchanged (U) – The exploit does not affect other components.
• Confidentiality (C): Low (L) – Limited unauthorized data access.
• Integrity (I): Low (L) – Limited unauthorized modification.
• Availability (A): None (N) – No impact on availability.

Threat Level: Medium. The vulnerability requires authentication but can be exploited with low privileges, making it a realistic threat for multi-user WordPress sites.

Deep Dive & Mechanics

The vulnerability resides in the Live Forms plugin’s access control logic. The plugin fails to properly validate user capabilities when processing AJAX requests or REST API endpoints related to form management. Specifically, functions that handle form creation, editing, deletion, or submission viewing do not enforce proper authorization checks, allowing any authenticated user (e.g., subscribers) to perform actions intended only for administrators or editors.

Root Cause: The plugin uses current_user_can() checks inconsistently or relies on nonce verification alone, which does not prevent low-privileged users from sending crafted requests.

Attack Vector: An attacker with a valid WordPress account (e.g., subscriber) can send specially crafted HTTP requests to the plugin’s endpoints, bypassing intended access controls.

Impact: Unauthorized access to form submissions (potentially containing sensitive user data), modification of form structures, or deletion of forms.

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 (Example):

add_action('wp_ajax_liveforms_save_form', 'liveforms_save_form');
function liveforms_save_form() {
    // No capability check
    $form_data = $_POST['form_data'];
    // Process and save form
}

Patched Code (Example):

add_action('wp_ajax_liveforms_save_form', 'liveforms_save_form');
function liveforms_save_form() {
    if (!current_user_can('manage_options')) {
        wp_die('Unauthorized', 403);
    }
    $form_data = $_POST['form_data'];
    // Process and save form
}

The patched version adds a capability check (manage_options) before processing the request, ensuring only administrators can perform the action.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• A WordPress site with Live Forms plugin version <= 4.8.4.
• A valid user account with low privileges (e.g., subscriber).

Exploitation Steps:

1. Log in as a low-privileged user.
2. Identify the vulnerable AJAX action (e.g., liveforms_save_form).
3. Craft a POST request using a tool like curl or Burp Suite:

   curl -X POST \
     -d "action=liveforms_save_form&form_data=malicious_data" \
     -b "wordpress_logged_in_cookie=..." \
     http://target.com/wp-admin/admin-ajax.php
   

4. Observe unauthorized access to form data or settings.

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

Blue Team (Detection & Defense)

Detection:

• Monitor for unusual AJAX requests from low-privileged users to sensitive plugin endpoints.
• Look for HTTP 403 errors followed by successful requests to the same endpoint (indicating bypass attempts).
• Use the detection rules provided in the Detection Engineering section.

Defense:

• Immediately restrict access to the plugin’s admin pages via .htaccess or a Web Application Firewall (WAF) until a patch is applied.
• Disable the plugin if not critical.
• Implement additional capability checks via a custom plugin or mu-plugin.

Indicators of Compromise (IOCs)

• Network IOCs:
  • POST requests to /wp-admin/admin-ajax.php with action=liveforms_* parameters from non-admin users.
  • Unusual patterns in form submission data (e.g., unexpected modifications).
• File IOCs:
  • Modified plugin files in /wp-content/plugins/live-forms/ (check file integrity).
• Log IOCs:
  • WordPress debug log entries showing current_user_can() failures or unauthorized access attempts.

Detection Engineering

YARA Rule

rule CVE_2025_39560_LiveForms_MissingAuth {
    meta:
        description = "Detects exploitation attempts for CVE-2025-39560 in Live Forms plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-39560"
    strings:
        $ajax_action = "liveforms_" ascii wide nocase
        $admin_ajax = "admin-ajax.php" ascii wide nocase
        $unauthorized = "Unauthorized" ascii wide nocase
    condition:
        $ajax_action and $admin_ajax and not $unauthorized
}

Sigma Rule

title: CVE-2025-39560 Live Forms Missing Authorization Exploitation
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects unauthorized AJAX requests to Live Forms 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=liveforms_'
    condition: selection
falsepositives:
    - Legitimate admin actions (rare)
level: medium

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2025-39560 Live Forms Missing Authorization Exploitation";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"admin-ajax.php"; http_uri;
    content:"action=liveforms_"; http_client_body;
    classtype:attempted-user;
    sid:1000001;
    rev:1;
    reference:cve,2025-39560;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin if it is not essential for business operations.
2. Restrict access to the plugin’s admin pages using .htaccess or a WAF rule:

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

3. Monitor logs for suspicious AJAX requests.

Long-term Fix:

• Apply the official patch once released by the vendor.
• If no patch is forthcoming, consider replacing the plugin with an alternative that has active security maintenance.

Workaround:

• Implement a custom mu-plugin that adds capability checks to all liveforms_* AJAX actions:

  add_action('init', function() {
      $actions = ['liveforms_save_form', 'liveforms_delete_form', 'liveforms_get_submissions'];
      foreach ($actions as $action) {
          add_action("wp_ajax_$action", function() {
              if (!current_user_can('manage_options')) {
                  wp_die('Unauthorized', 403);
              }
          }, 0);
      }
  });
  

Valters IT
Cyber Threat Intelligence & DevSecOps