ProFTPD 1.2.9 treats the Allow and Deny directives for CIDR based ACL entries as if they were AllowAll, which could allow FTP clients to bypass intended access restrictions.
https://exchange.xforce.ibmcloud.com/vulnerabilities/16038
http://www.securityfocus.com/bid/10252
http://www.mandriva.com/security/advisories?name=MDKSA-2004:041
http://secunia.com/advisories/11527
http://marc.info/?l=bugtraq&m=108335051011341&w=2