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 (Pro) & 2.2.8 (Free). This is due to missing or incorrect nonce validation on the save_virtual_event_settings function. This makes it possible for unauthenticated attackers to modify virtual event settings via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.