UDP Port 21 – FTP (File Transfer Protocol)

About UDP Port 21

Port 21 is registered with the Internet Assigned Numbers Authority (IANA) for ftp. The IANA description reads: ‘File Transfer Protocol [Control]’. This port appears in 0 IDS rules and does not have notable malware activity indicators in our data.

Data Sources

This information is compiled from: IANA Service Name and Transport Protocol Port Number Registry, Emerging Threats Open Ruleset (BSD 2-Clause / GPLv2 per SID range), Snort Community Rules (GPLv2), and MITRE ATT&CK (Apache 2.0).