CVE-2026-5427 Missing authorization in Kubio AI Page Builder
Authenticated contributors can bypass upload restrictions to import external files into the media library via REST API block attributes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-5427?
CVE-2026-5427 is a medium-severity missing authorization vulnerability in extendthemes Kubio AI Page Builder, published on 17 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
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.
Weakness: CWE-862
Which versions are affected by CVE-2026-5427?
How do I fix CVE-2026-5427?
No fix has been published for CVE-2026-5427 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-5427 being exploited?
There is no known exploitation of CVE-2026-5427 in the wild and no public exploit code.
Sources
Also known as GHSA-69wp-qf6q-mf28.