Vulnerability · Published Apr 17, 2026 · Assigned by Wordfence
CVE-2026-5427Kubio AI Page Builder <= 2.7.2 - Missing Authorization to Authenticated (Contributor+) Limited File Upload via Kubio Block Attributes
Medium 5.3
In plain English
A medium-severity missing authorization in Kubio AI Page Builder from extendthemes. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities).
Official description
The Kubio plugin for WordPress is vulnerable to Arbitrary File Upload in versions up to and including 2.7.2. This is due to insufficient capability checks in the kubio_rest_pre_insert_import_assets() function, which is hooked to the rest_pre_insert_{post_type} filter for posts, pages, templates, and template parts. When a post is created or updated via the REST API, Kubio parses block attributes looking for URLs in the 'kubio' attribute namespace and automatically imports them via importRemoteFile() without verifying the user has the upload_files capability. This makes it possible for authenticated attackers with Contributor-level access and above to bypass WordPress's normal media upload restrictions and upload files fetched from external URLs to the media library, creating attachment posts in the database.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| extendthemes | Kubio AI Page Builder | 0 – through 2.7.2 |
Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
References
- https://www.wordfence.com/threat-intel/vulnerabilities/id/d8096f3c-e1a9-424f-af10-3e80212db985?source=cve
- https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/src/Core/Importer.php#L546
- https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/src/Core/Importer.php#L546
- https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/importer/importer-filters/kubio-blocks.php#L20
- https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/importer/importer-filters/kubio-blocks.php#L20
- https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/filters/post-insert.php#L17
- https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/filters/post-insert.php#L17
- https://plugins.trac.wordpress.org/changeset/3506647/kubio/trunk/lib/src/Core/Importer.php