CVE-2026-6279
published 2026-05-21CVE-2026-6279: The Avada Builder (fusion-builder) plugin for WordPress is vulnerable to Unauthenticated Remote Code Execution via PHP Function Injection in versions up to and…
PriorityP186critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
ITWEXPLOITVulnCheck KEVInitial access
Exploited in the wild
EPSS
2.39%
83.8th percentile
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.
Affected
1 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| themefusion | avada_builder | <= 3.15.2 | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vulncheck9.8CRITICAL
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VulDB
themefusion Avada Builder Plugin up to 3.15.2 on WordPress AJAX Endpoint get_value injection
vuldb·2026-05-21·CVSS 9.8
CVE-2026-6279 [CRITICAL] themefusion Avada Builder Plugin up to 3.15.2 on WordPress AJAX Endpoint get_value injection
A vulnerability, which was classified as critical, was found in themefusion Avada Builder Plugin up to 3.15.2 on WordPress. This affects the function Fusion_Builder_Conditional_Render_Helper::get_value of the component AJAX Endpoint. Such manipulation leads to injection.
This vulnerability is uniquely identified as CVE-2026-6279. The attack can be launched remotely. No exploit exists.
You should upgrade the affected component.
GHSA
GHSA-f53p-382v-8pj7: The Avada Builder (fusion-builder) plugin for WordPress is vulnerable to Unauthenticated Remote Code Execution via PHP Function Injection in versions
ghsa_unreviewed·2026-05-21
CVE-2026-6279 [CRITICAL] CWE-74 GHSA-f53p-382v-8pj7: The Avada Builder (fusion-builder) plugin for WordPress is vulnerable to Unauthenticated Remote Code Execution via PHP Function Injection in versions
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
VulnCheck
theme-fusion avada_builder Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
vulncheck·2026·CVSS 9.8
CVE-2026-6279 [CRITICAL] theme-fusion avada_builder Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
theme-fusion avada_builder Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
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 (`f
No detection rules found.
Nuclei
Avada Builder (fusion-builder) <= 3.15.2 - Unauthenticated RCE via PHP Function Injection
nuclei·CVSS 9.8
CVE-2026-6279 [CRITICAL] Avada Builder (fusion-builder) <= 3.15.2 - Unauthenticated RCE via PHP Function Injection
Avada Builder (fusion-builder) <= 3.15.2 - Unauthenticated RCE via PHP Function Injection
The Avada Builder (fusion-builder) plugin for WordPress (versions <= 3.15.2) is vulnerable to unauthenticated remote code execution via PHP function injection. The fusion_get_widget_markup AJAX action is registered for unauthenticated users (wp_ajax_nopriv_fusion_get_widget_markup) and is gated only by check_ajax_referer('fusion_load_nonce') - which validates nonce integrity, not user identity. That nonce is minted with wp_create_nonce() for user ID 0 and is deterministically inlined into the JavaScript (fusionPostCardsVars / fusionTableOfContentsVars, key "nonce") of any public page that renders a [fusion_post_cards] or [fusion_table_of_contents] shortcode. The attacker-controlled render_logics para
No writeups or analysis indexed.
https://avada.com/documentation/avada-changelog/https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/inc/class-fusion-builder.php#L7551https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1083https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1531https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/shortcodes/fusion-widget.php#L389https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/shortcodes/fusion-widget.php#L44https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/class-fusion-builder.php#L7551https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1083https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1531https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/shortcodes/fusion-widget.php#L389https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/shortcodes/fusion-widget.php#L44https://www.wordfence.com/threat-intel/vulnerabilities/id/5dc72d78-d47c-4b36-8d69-8672e15ddf8c?source=cve
2026-05-21
Published
Exploited in the wild