Input validation vulnerability in Newspack Newsletters 2.13.2

The plugin called “Newspack Newsletters” on WordPress has a security issue in versions up to 2.13.2. This is because it does not properly check for a special security code, making it possible for someone without permission to do things they shouldn’t be able to do. This could happen if the attacker tricks the person who runs the website into doing something, like clicking on a link.