The Petje.af plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to and including 2.1.8. This is due to missing nonce validation in the ajax_revoke_token() function which handles the 'petjeaf_disconnect' AJAX action. The function performs destructive operations including revoking OAuth2 tokens, deleting user meta, and deleting WordPress user accounts (for users with the 'petjeaf_member' role) without verifying the request originated from a legitimate source. This makes it possible for unauthenticated attackers to force authenticated users to delete their Petje.af member user accounts via a forged request granted the victim clicks on a link or visits a malicious site.