The popular WordPress plugin WP Super Cache has been found to have a cross-site scripting (XSS) vulnerability in versions prior to 1.4.4. On sites with outdated versions, it is possible for an attacker to take complete control of the WordPress site. Please note: this vulnerability only affects users which have installed WP Super Cache. However, if you are unsure if you use the plugin or not you should still take precautions to protect your site.
Thankfully, this is vulnerability is simple to address; version 1.4.4, available now, contains a patch.