Directly from WHM panel
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 http://support.cpanel.net
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 http://support.cpanel.net