GoodTech FTP server 3.0.1.2.1.0 and earlier allows remote attackers to cause a denial of service via a flood of connections to the server, which causes it to crash.
https://exchange.xforce.ibmcloud.com/vulnerabilities/5984
http://www.securityfocus.com/bid/2270
http://archives.neohapsis.com/archives/bugtraq/2001-01/0350.html