Update the WordPress WatchTowerHQ plugin to the latest available version (at least 3.6.16).
Dave Jong (Patchstack) discovered and reported this Arbitrary File Deletion vulnerability in WordPress WatchTowerHQ Plugin. This could allow a malicious actor to delete files from your website. If core files are deleted from your website, it could cause your site to break and stop functioning. This vulnerability has been fixed in version 3.6.16.