Input validation vulnerability in WordPress 3.6.1

WordPress Core, the software that runs the website, has a security vulnerability. This means that it is possible for an unauthenticated user to perform certain actions on the website under the identity of another user. This is due to the fact that in versions of WordPress before 6.0.3, when using wp-trackback.php (a file that helps track changes to the website), the identity of the user whose cookies were sent with the request would be assumed. To fix this, new versions of WordPress will assign the identity of an unauthenticated user (meaning one who isn’t logged in) to the ID of 0.