The ftp_PORT function in FTPServer.py in pyftpdlib before 0.2.0 does not prevent TCP connections to privileged ports if the destination IP address matches the source IP address of the connection from the FTP client, which might allow remote authenticated users to conduct FTP bounce attacks via crafted FTP data, as demonstrated by an FTP bounce attack against a NAT server, a related issue to CVE-1999-0017.

BlueArc-FTPD in BlueArc Titan 2x00 devices with firmware 4.2.944b allows remote attackers to redirect traffic to other sites (aka FTP bounce) via the PORT command, a variant of CVE-1999-0017.

The FTP server in the NEC MultiWriter 1700C allows remote attackers to redirect traffic to other sites (aka FTP bounce) via the PORT command, a variant of CVE-1999-0017.

FTP servers can allow an attacker to connect to arbitrary ports on machines other than the FTP client, aka FTP bounce.