CVE-2026-5427

Kubio AI Page Builder <= 2.7.2 - Missing Authorization to Authenticated (Contributor+) Limited File Upload via Kubio Block Attributes

2026-04-16 15:06
oolongeya

Strategic Overview

Status
Patched in 2.7.3
Affected Plugin
Kubio AI Page Builder
Affected Version
<= 2.7.2
CVSS
5.3Medium
Weakness type
CWE-862 · Missing Authorization
CVE
CVE-2026-5427
View all Kubio AI Page Builder vulnerabilities

At a glance

CVE-2026-5427 is a medium-severity Missing Authorization vulnerability in the Kubio AI Page Builder WordPress plugin, affecting versions <= 2.7.2. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 2.7.3; sites on affected versions should update now. Disclosed April 2026, reported by oolongeya.

Vulnerability Overview

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.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-862: Missing Authorization

Kubio AI Page Builder <= 2.7.2 carries this weakness at kubio, and reaching it takes an account at Contributor level or above. A missing authorization check means a function is reachable by anyone who can reach the endpoint, because the code never asks whether the caller is allowed to perform the action.

Any user who can reach the endpoint gets to run an action reserved for higher-privileged roles, from reading protected data to changing settings or content. For Kubio AI Page Builder the fix is 2.7.3: builds <= 2.7.2 are affected, anything from 2.7.3 onward is not.

Remediation

Update to version 2.7.3, or a newer patched version

How does WordSec protect against this?

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: Kubio AI Page Builder 2.7.3 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

Related records

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