extendthemes Kubio AI Page Builder Plugin up to 2.8.5 on WordPress check_ajax_referer authorization

Summaryinfo

A vulnerability has been found in extendthemes Kubio AI Page Builder Plugin up to 2.8.5 and classified as problematic. The impacted element is the function check_ajax_referer. The manipulation leads to authorization. This vulnerability is traded as CVE-2026-16779. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in extendthemes Kubio AI Page Builder Plugin up to 2.8.5. This issue affects the function check_ajax_referer. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. Impacted is integrity. The summary by CVE is:

The Kubio AI Page Builder plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 2.8.5. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with contributor-level access and above, to overwrite front-page configuration options (show_on_front, page_on_front, and page_for_posts), rewrite primary navigation menu items, replace template parts, and overwrite the Kubio global-data post. Although a nonce check via check_ajax_referer() is present, the nonce is unconditionally emitted into window.kubioUtilsData for every user who can load the block editor, making it harvestable by any Contributor and therefore an ineffective authorization barrier.

It is possible to read the advisory at wordfence.com. The identification of this vulnerability is CVE-2026-16779 since 07/23/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/16/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• WordPress Plugin

Vendor

• extendthemes

Name

• Kubio AI Page Builder Plugin

Version

• 2.8.0
• 2.8.1
• 2.8.2
• 2.8.3
• 2.8.4
• 2.8.5

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

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Entryinfo

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