CVE-2026-5427 (GCVE-0-2026-5427)

Vulnerability from cvelistv5 – Published: 2026-04-17 03:36 – Updated: 2026-04-17 18:48
VLAI?
Title
Kubio AI Page Builder <= 2.7.2 - Missing Authorization to Authenticated (Contributor+) Limited File Upload via Kubio Block Attributes
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.
Severity ?
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
Assigner
References
Impacted products
Vendor Product Version
extendthemes Kubio AI Page Builder Affected: 0 , ≤ 2.7.2 (semver)
Create a notification for this product.
Credits
SeungRyeol Baek
Show details on NVD website
To clipboard 

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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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