I have had this message lurking on top of my WHM Panel. Maybe some my take hed to the warning since most of us do use it
Security At this time, it is recommended that all customers using proftpd Switch to pure-ftpd as soon as possible to eliminate a potential security hole. Please note that all released versions of proftpd are belived to be affected and the exact problem is not yet known. Customers who experience the problems switching are welcomed to bypass the normal support procedure and submit a ticket directly at cpanel.net.