Avada (Fusion) Builder <= 3.15.2 — Unauthenticated Remote Code Execution via PHP Function Injection via 'render_logics' Shortcode Attribute via Widget AJAX Handler
CVE-2026-6279Published · Updated Action summary
Affected: ≤3.15.2Update to 3.15.3 or newer
All remediation steps- Severity
- Critical9.8
- CVSS
- 9.8CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HWhat does this vector mean?
AV:NAttack vector- Network
AC:LAttack complexity- Low
PR:NPrivileges required- None
UI:NUser interaction- None
S:UScope- Unchanged
C:HConfidentiality- High
I:HIntegrity- High
A:HAvailability- High
- Required access
- No account needed
- Exploit prediction (EPSS)
- No score
- CISA KEV
- Not listed
On this page8
Am I affected?
Avada (Fusion) Builder fusion-builder
- Affected≤ 3.15.2
- Patched in3.15.3
Update to 3.15.3 or newer.
You are affected if you run ≤ 3.15.2. Version 3.15.3 and later are not affected by this issue.
- Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Avada (Fusion) Builder.
- No admin access? Run a passive check of your site. It reads public files only.
- No account is needed to exploit this. Treat any exposed site on an affected version as at risk.
What to do
- Update to version 3.15.3, or a newer patched version
- Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
- Watch Avada (Fusion) Builder to get an email when the next vulnerability is published.
Advisory
Source description from Wordfence Intelligence, credited to Tin Pham (TF1T), Trong Pham (dtro), Hao Ngo.
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.
Exploits & references
Proof-of-concept & detection
No public proof-of-concept or detection template is known for this vulnerability.
Advisories & patches
- Advisorywordfence.com
Related CVEs
More in Avada (Fusion) Builder
All 33| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| High7.2 | Unauthenticated Stored Cross-Site Scripting via Form Notification Dynamic-Data action_hook ≤3.16.1Update to 3.16.2 | CVE-2026-84938 | |
| Medium6.4 | Authenticated (Contributor+) Stored Cross-Site Scripting via 'tab_index' and 'empty_notice' Shortcode Attributes ≤3.16.2Update to 3.16.3 | CVE-2026-104729 | |
| Medium5.3 | Unauthenticated Sensitive Information Exposure in 'args[link_target]' Parameter via {user_meta} Dynamic Data Token ≤3.16.1Update to 3.16.2 | CVE-2026-97471 | |
| Critical9.1 | Unauthenticated Arbitrary WordPress Action Invocation via '{action_hook}' Dynamic-Data Token in Form Field ≤3.16.1Update to 3.16.2 | CVE-2026-97670 | |
| Medium6.4 | Authenticated (Contributor+) Stored Cross-Site Scripting via 'size' Shortcode Attribute ≤3.15.6Update to 3.16 | CVE-2026-16654 |
- High7.2Unauthenticated Stored Cross-Site Scripting via Form Notification Dynamic-Data action_hook
≤3.16.1Update to 3.16.2
- Medium6.4Authenticated (Contributor+) Stored Cross-Site Scripting via 'tab_index' and 'empty_notice' Shortcode Attributes
≤3.16.2Update to 3.16.3
- Medium5.3Unauthenticated Sensitive Information Exposure in 'args[link_target]' Parameter via {user_meta} Dynamic Data Token
≤3.16.1Update to 3.16.2
- Critical9.1Unauthenticated Arbitrary WordPress Action Invocation via '{action_hook}' Dynamic-Data Token in Form Field
≤3.16.1Update to 3.16.2
- Medium6.4Authenticated (Contributor+) Stored Cross-Site Scripting via 'size' Shortcode Attribute
≤3.15.6Update to 3.16
Timeline
CVE published
Severity critical, CVSS 9.8
Record last updated
Sources & licenses
Wordfence record- Vulnerability data
- Wordfence Intelligence. [object Object] Licensed under the CC BY-SA 4.0.
- CVE® identifiers
- [object Object]. Used under the CVE Program. CVE® is a registered trademark of The MITRE Corporation.
- CVSS / CWE
- National Vulnerability Database (NVD), shown unmodified. This product uses the NVD API but is not endorsed or certified by the NVD.
- VulnCrest content
- Summary, remediation guidance and page layout © VulnCrest. Not sourced from NVD.