CVE-2025-48276: Visual Composer Website Builder XSS Flaw

CVE-2025-48276 Overview

CVE-2025-48276 is a stored Cross-Site Scripting (XSS) vulnerability in the Visual Composer Website Builder plugin for WordPress. The flaw stems from improper neutralization of input during web page generation [CWE-79]. It affects all versions of the plugin up to and including 45.11.0. An authenticated attacker with low privileges can inject persistent JavaScript payloads that execute in the browsers of users who view affected pages. Successful exploitation requires user interaction and can lead to session compromise, content manipulation, and pivoting to higher-privileged accounts.

Critical Impact
Authenticated attackers can inject persistent JavaScript that executes in administrator browsers, enabling session hijacking and further compromise of the WordPress site.

Affected Products

Visual Composer Website Builder plugin for WordPress
All versions from initial release through 45.11.0
WordPress installations with the plugin enabled

Discovery Timeline

2025-05-19 - CVE-2025-48276 published to the National Vulnerability Database (NVD)
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-48276

Vulnerability Analysis

The vulnerability is a stored XSS issue in the Visual Composer Website Builder plugin. The plugin fails to properly sanitize or encode user-supplied input before it is stored and later rendered in generated web pages. When a victim loads a page containing the malicious content, the browser parses and executes the attacker-controlled JavaScript in the context of the WordPress site.

Because the payload is persistent, it fires each time an affected page is rendered. The scope-changed attack allows script execution across the WordPress admin interface, giving attackers access to authenticated session data, cookies, and DOM state belonging to higher-privileged users.

Root Cause

The root cause is missing or insufficient output encoding when the plugin renders builder-generated content. Input passed through plugin fields is written into the response without HTML entity encoding or context-aware escaping, violating standard XSS prevention practices for template output.

Attack Vector

Exploitation requires an authenticated user with contributor or editor-level access to the WordPress instance. The attacker submits crafted content through Visual Composer fields, which persists in the database. When an administrator or other visitor loads the affected page, the injected script executes in their browser. See the Patchstack Vulnerability Report for further technical detail.

Detection Methods for CVE-2025-48276

Indicators of Compromise

WordPress posts, pages, or Visual Composer templates containing <script> tags, javascript: URIs, or event handler attributes such as onerror, onload, and onclick.
Unexpected outbound HTTP requests from administrator browsers to attacker-controlled domains following page views.
New administrator accounts, modified user roles, or unauthorized changes to plugin and theme files.

Detection Strategies

Audit the wp_posts and Visual Composer metadata tables for stored HTML fragments containing scripting primitives.
Deploy a Web Application Firewall (WAF) with rules that inspect and alert on XSS payload patterns submitted to WordPress editor endpoints.
Monitor plugin version inventory across managed WordPress sites and flag installations running 45.11.0 or earlier.

Monitoring Recommendations

Enable WordPress audit logging to record post edits, user role changes, and plugin activity by low-privileged accounts.
Track browser console errors and Content Security Policy (CSP) violation reports from administrator sessions.
Correlate authentication events with content modifications to identify anomalous contributor or editor behavior.

How to Mitigate CVE-2025-48276

Immediate Actions Required

Update the Visual Composer Website Builder plugin to a version later than 45.11.0 as soon as a fixed release is available from the vendor.
Restrict contributor, author, and editor role assignments to trusted users and review existing accounts for unexpected privileges.
Review recently modified posts and Visual Composer templates for injected script content and remove any malicious entries.

Patch Information

Refer to the Patchstack Vulnerability Report for the latest patch status and vendor-supplied fixed version. Apply the update through the WordPress plugin manager or by replacing the plugin files with the patched release.

Workarounds

Disable the Visual Composer Website Builder plugin until an updated version is installed.
Deploy a strict Content Security Policy (CSP) that blocks inline script execution and restricts allowed script sources.
Place the WordPress site behind a WAF configured with WordPress-specific XSS signatures to filter malicious input submissions.

bash

# Example CSP header to reduce stored XSS impact
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'"