---
id: "CVE-2026-104729"
kind: "vulnerability"
aliases: ["CVE-2026-104729"]
title: "Avada Fusion Builder WordPress plugin: stored XSS via shortcode attributes"
severity: "medium"
cvss: 6.4
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["avada", "fusion-builder", "package", "self-hosted", "wordpress"]
not_affected_if: ["no-contributor-accounts", "plugin-newer-than-3.16.2", "plugin-not-installed"]
published_at: "2026-10-28T07:16:43+00:00"
first_seen_at: "2026-10-28T07:31:37+00:00"
updated_at: "2026-10-28T07:33:11+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-104729", "first_seen_at": "2026-10-28T07:31:37+00:00"}]
---

# Avada Fusion Builder WordPress plugin: stored XSS via shortcode attributes

The Avada (Fusion) Builder WordPress plugin up to and including 3.16.2 fails to sanitize the tab_index and empty_notice parameters. An authenticated contributor can save a script that runs in the browser of anyone who opens the injected page.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed Avada or Fusion Builder plugin version in the WordPress admin under Plugins; `3.16.2` and earlier are affected per the sources.
- Search page content for shortcodes using tab_index or empty_notice attributes containing script tags.

## Fix

- Update the Avada (Fusion) Builder plugin to a version newer than `3.16.2`; the fixed version is unknown from the sources.
- Until patched, limit contributor-level accounts and review pages that were edited by them.

## Timeline

- 2026-10-28T07:31:37+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-104729

## From the sources

The Avada (Fusion) Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'tab_index, empty_notice' parameter in all versions up to, and including, 3.16.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. wp_kses_post does not strip the payload on save because the dangerous characters reside within shortcode attribute text between square brackets, which kses treats as plain text rather than HTML markup.

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