CVE-2026-19698: GutenKit < 2.5.1 - Contributor+ Stored CSS Injection
The GutenKit WordPress plugin before 2.5.1 does not validate or escape style settings saved against a post before using them to build the CSS it outputs on the front end, allowing users with the Contributor role and above to inject arbitrary CSS into pages served to other users and to anonymous visitors. JavaScript execution is not possible at that role, so the impact is limited to defacement, interface redressing and forcing external resources to load.
Affected Software
Event History
Frequently Asked Questions
Who can exploit this issue and who can be affected by the injected content?
A user with the WordPress Contributor role or higher can inject CSS through affected GutenKit style settings. The resulting CSS can be served to other logged-in users and anonymous visitors viewing the affected pages.
What can an attacker do with the injected CSS?
The stated impact is limited to page defacement, interface redressing, and causing external resources to load. JavaScript execution is not possible at the Contributor role described here.
Are installations running GutenKit 2.5.1 affected?
The issue affects GutenKit versions before 2.5.1. Version 2.5.1 is not identified as affected by the provided data.