Cross site request forgery (csrf)

The ImageRecycle pdf & image compression plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 3.1.13. This is due to missing or incorrect nonce validation on the enableOptimization function. This makes it possible for unauthenticated attackers to enable image optimization via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.