The Crypto plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 2.15. This is due to missing nonce validation in the 'crypto_connect_ajax_process::check' function. This makes it possible for unauthenticated attackers to log in as any existing user on the site, such as an administrator via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.