CVE-2021-39203
WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. In affected versions authenticated users who don’t have permission to view private post types/data can bypass restrictions in the block editor under certain conditions. This affected WordPress 5.8 beta during the testing period. It’s fixed in the final 5.8 release.
Source: CVE-2021-39203