WPFront User Role Editor <= 4.2.1 - Cross-Site Request Forgery to Privilege Escalation via whitelist_options Function

The WPFront User Role Editor plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 4.2.1. This is due to missing or incorrect nonce validation on the whitelist_options() function. This makes it possible for unauthenticated attackers to update the default role option that can be leveraged for privilege escalation via a forged request granted they can trick a site administrator into performing an action such as clicking on a link. This is only exploitable on multisite instances.