Post Grid and Gutenberg Blocks 2.2.87 - 2.2.90 - Authenticated (Subscriber+) Privilege Escalation

The Post Grid and Gutenberg Blocks plugin for WordPress is vulnerable to privilege escalation in all versions 2.2.87 to 2.2.90. This is due to the plugin not properly restricting what user meta values can be updated and ensuring a form is active. This makes it possible for authenticated attackers, with subscriber-level access and above, to update their user meta to become an administrator.