Cross site request forgery (csrf)

The EventON - WordPress Virtual Event Calendar Plugin plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 4.5.4 (for Pro) & 2.2.7 (for Free). This is due to missing or incorrect nonce validation on the evo_eventpost_update_meta function. This makes it possible for unauthenticated attackers to update arbitrary post metadata via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.