The WP OAuth Server (OAuth Authentication) WordPress plugin before 4.3.0 has a flawed CSRF and authorisation check when deleting a client, which could allow any authenticated users, such as subscriber to delete arbitrary client.

The WP OAuth Server (OAuth Authentication) WordPress plugin before 4.2.5 does not have CSRF check when deleting a client, and does not ensure that the object to be deleted is actually a client, which could allow attackers to make a logged in admin delete arbitrary client and post via a CSRF attack.

The oauth2-provider plugin before 3.1.5 for WordPress has incorrect generation of random numbers.