CVE-2026-6279

Summary

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 Software

VendorProductVersion RangeStatus
themefusionAvada (Fusion) Builder0 <= 3.15.2affected

Weaknesses

  • CWE-74: CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: total

References