CVE intelligence and bounded remediation

CVE-2026-12902 — Kadence Blocks security vulnerability

Medium CVSS 4.3

The Kadence Blocks — Page Builder Toolkit for Gutenberg Editor plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 3.7.7. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with contributor-level access and above, to create arbitrary Media Library attachments by downloading remote images to the site's uploads directory via wp_upload_bits() and wp_insert_attachment(), bypassing the upload_files capability boundary.

Severity
Medium
CVSS
4.3 (3.1)
Published
2026-07-01
CISA KEV
Not currently listed
Ecosystem
php/wordpress
Weaknesses
CWE-862

Affected products

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Matched remediation archetype

Authorization bypass, IDOR, and cross-tenant access

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Check exposure

  • Map object and action authorization checks across API, UI, batch, import/export, and background-job paths.
  • Identify tenant, ownership, role, and policy boundaries for affected resources and administrative operations.
  • Use synthetic fixtures to compare intended access matrices without accessing another user's real data.

Remediate safely

  • Enforce server-side authorization at each resource access and state transition using the authenticated principal and trusted tenant context.
  • Scope data queries by tenant and ownership; treat client-supplied identifiers, roles, and policy claims as untrusted.
  • Add deny-by-default policy tests for horizontal and vertical access across every affected transport.

Authoritative sources

Complete CVE record and remediation plan

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