Reported vulnerability

Avada (Fusion) Builder <= 3.15.2 - Unauthenticated Remote Code Execution via PHP Function Injection via 'render_logics' Shortcode Attribute via Widget AJAX Handler

Q: Which versions of Avada (Fusion) Builder are affected?

Wordfence lists these affected versions: Start version unspecified, through 3.15.2. Use the version checker above to compare your installed release with this report.

Q: Is a fix available for Avada (Fusion) Builder?

Wordfence reports a fix for this issue in Avada (Fusion) Builder. It lists these fixed versions: 3.15.3. Back up your website and test the recommended update before applying it to your live site.

Q: Where can I find my installed plugin version?

In WordPress, open Plugins > Installed Plugins and find the version shown beneath the plugin name.

Published 20 May 2026

Updated 21 May 2026

CVE-2026-6279

Compare your installed software with the affected versions below. Follow the source’s remediation guidance and test an available update after taking a backup. A database entry describes a reported issue; it does not establish whether a particular website has been compromised.

Does this affect my version?

Check your installed version against this advisory. This compares the report’s version ranges and does not scan your website.

Wordfence advisory

critical · CVSS 9.8

The Avada Builder (fusion-builder) plugin for WordPress is vulnerable to Unauthenticated Remote Code Execution via PHP Function Injection in versions up to and including 3.15.2. This is due to the `wp_conditional_tags` case in `Fusion_Builder_Conditional_Render_Helper::get_value()` passing attacker-controlled values from a base64-decoded JSON blob directly to `call_user_func()` without any allowlist validation. This is exploitable by unauthenticated attackers through the `fusion_get_widget_markup` AJAX endpoint, which is registered for non-privileged (unauthenticated) users via `wp_ajax_nopriv_fusion_get_widget_markup`. The endpoint is protected only by a nonce (`fusion_load_nonce`), but this nonce is generated for user ID 0 and is deterministically exposed in the JavaScript output of any public-facing page containing a Post Cards (`[fusion_post_cards]`) or Table of Contents (`[fusion_table_of_contents]`) element. This makes it possible for unauthenticated attackers to execute arbitrary code on affected sites.

Severity vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Avada (Fusion) Builder

Software: plugin · fusion-builder
Affected versions: Start version unspecified, through 3.15.2
Fix availability: Fix available
Fixed versions: 3.15.3

Recommended action

Update to version 3.15.3, or a newer patched version

Further references (1)

wordfence.com/threat-intel/vulnerabilities/id/5dc72d78-d47c-4b36-8d69-8672e15ddf8c?source=api-prod

Data sources and licences

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CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.

Read licence terms

Source: Wordfence

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Questions about this vulnerability

Which versions of Avada (Fusion) Builder are affected?

Wordfence lists these affected versions: Start version unspecified, through 3.15.2. Use the version checker above to compare your installed release with this report.

Is a fix available for Avada (Fusion) Builder?

Wordfence reports a fix for this issue in Avada (Fusion) Builder. It lists these fixed versions: 3.15.3. Back up your website and test the recommended update before applying it to your live site.

Where can I find my installed plugin version?

In WordPress, open Plugins > Installed Plugins and find the version shown beneath the plugin name.

Does an affected version mean my website has been hacked?

An affected version means the installed release matches a vulnerability described in this report. It does not show whether anyone has exploited it on your website. The checker compares version numbers with stored reports; it does not inspect your website.

These reports cover at least one of the same plugins, themes or WordPress core. Check each report’s affected versions separately.

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