CVE-2026-5427 json
Kubio AI Page Builder <= 2.7.2 - Missing Authorization to Authenticated (Contributor+) Limited File Upload via Kubio Block Attributes
published 2026-04-17 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-23358
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 45%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.54% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected products
- extendthemes Kubio AI Page Builder
Classification
- Weakness
-
- CWE-862 Missing Authorization
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/d8096f3c-e1a9-424f-af10-3e80212db985?source=cve
- plugins.trac.wordpress.org /browser/kubio/trunk/lib/src/Core/Importer.php#L546
- plugins.trac.wordpress.org /browser/kubio/tags/2.7.1/lib/src/Core/Importer.php#L546
- plugins.trac.wordpress.org /browser/kubio/trunk/lib/importer/importer-filters/kubio-blocks.php#L20
- plugins.trac.wordpress.org /browser/kubio/tags/2.7.1/lib/importer/importer-filters/kubio-blocks.php#L20
- plugins.trac.wordpress.org /browser/kubio/trunk/lib/filters/post-insert.php#L17
- plugins.trac.wordpress.org /browser/kubio/tags/2.7.1/lib/filters/post-insert.php#L17
- plugins.trac.wordpress.org /changeset/3506647/kubio/trunk/lib/src/Core/Importer.php
Sources
- CVE List CVE-2026-5427
- NVD CVE-2026-5427
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.