Shield Security <= 21.0.8 - Cross-Site Request Forgery to SQL Injection

The Shield Security plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 21.0.8. This is due to the plugin allowing nonce verification to be bypassed via user-supplied parameter in the 'isNonceVerifyRequired' function. This makes it possible for unauthenticated attackers to execute SQL injection attacks, extracting sensitive information from the database, via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.