Kirby is an open-source content management system. Prior to versions 4.9.0 and 5.4.0, Kirby's user permissions control which user role is allowed to perform specific actions to content models in the CMS. These permissions are defined for each role in the user blueprint (`site/blueprints/users/...`). It is also possible to customize the permissions for each target model in the model blueprints (such as in `site/blueprints/pages/...`) using the `options` feature. The permissions and options together control the authorization of user actions. For pages, Kirby provides the `pages.create` and `pages.changeStatus` permissions (among others). In affected releases, Kirby checked these permissions independently and only for the respective action. However the `changeStatus` permission didn't take effect on page creation. New pages are created as drafts by default and need to be published by changing the page status of an existing page draft. This is ensured when the page is created via the Kirby Panel. However the REST API allows to override the `isDraft` flag when creating a new page. This allowed authenticated attackers with the `pages.create` permission to immediately create published pages, bypassing the normal editorial workflow. The problem has been patched in Kirby 4.9.0 and Kirby 5.4.0. Kirby has updated the `Options` logic to no longer double-resolve queries in option values coming from `OptionsQuery` or `OptionsApi` sources. Kirby now only resolves queries that are directly…

Affected: Packagist: getkirby/cms

### TL;DR

This vulnerability affects all Kirby sites that use option fields (`checkboxes`, `color`, `multiselect`, `select`, `radio`, `tags` or `toggles`) with options from a query or API whose values may not be fully trusted. It also affects direct uses of the `OptionsApi` or `OptionsQuery` classes of Kirby's `Options` package from plugin or site code. The attack requires either an attacker in the group of authenticated Panel users or user interaction of another authenticated user.

**This vulnerability is of high severity for affected sites.**

Users' Kirby sites are *not* affected if they are not using any of the mentioned fields or the `Options` package, if all options are defined statically in the blueprints or if all dynamically gathered options are to be trusted.

----

### Introduction

Server-Side Template Injection vulnerabilities (SSTI) occur when user input is embedded in a template in an unsafe manner and results in remote code execution on the server.

Injected user input is wrongly treated as a template command instead of as a literal string of text. This allows attackers to query arbitrary information from the affected system or call arbitrary methods to perform actions.

In a Kirby site this can be used to access protected site information, alter site content or break site behavior.

### Impact

Kirby provides field types (`checkboxes`, `color`, `multiselect`, `select`, `radio`, `tags` and `toggles`) that offer a fixed set of options from a configured list.…