Input validation vulnerability in SpamReferrerBlock 2.22

The SpamReferrerBlock plugin for WordPress has a security flaw in versions up to and including 2.22. This flaw allows unauthenticated attackers to make unauthorized changes to a website without the website administrator knowing. Attackers can do this by creating a link that the website administrator clicks on, which will then allow the attacker to make changes. This is possible because the plugin does not have the right security measures in place to prevent this type of attack.