Input validation vulnerability in Disable User Login 1.3.7

The Disable User Login plugin for WordPress is vulnerable to security issues. In versions up to and including 1.3.7, it is possible for unauthenticated attackers to make a forged request that could allow them to perform an unauthorized action. This is because the plugin does not include the proper validation measures to prevent this. An example of this would be if the attacker tricked a site administrator into clicking on a malicious link.