Easy Email Subscription <= 1.3 - Cross-Site Request Forgery to Arbitrary Subscriber Deletion

The Easy Email Subscription plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 1.3. This is due to missing or incorrect nonce validation on the show_editsub_page() function. This makes it possible for unauthenticated attackers to delete arbitrary subscribers via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.