Input validation vulnerability in Newsletter – Send awesome emails from WordPress 3.2.6

The Newsletter plugin for WordPress is vulnerable to a type of cyber attack called Reflected Cross-Site Scripting. This type of attack occurs when a malicious code is put into a link that can be clicked on. If a user clicks on the link, the malicious code will be executed. This vulnerability affects versions of the Newsletter plugin up to 3.2.6. The vulnerability is caused by the plugin not properly sanitizing and escaping user input. This means that attackers are able to inject malicious code into the plugin which then can be executed if someone clicks on the link.