← Port Encyclopedia
21
FTP
TCP
File Transfer
High Risk
FTP control channel — authentication in cleartext, anonymous login risks, bounce attacks
🔍 How to Scan Port 21
nmap -sV -p 21 target
nmap -sV -sC --script=banner -p 21 target
nc -zv target 21
🛡️ Security Considerations
- Scan port 21 with
nmap -sVto identify the exact service and version - If FTP is not needed, close or firewall this port immediately
- Check for default credentials if a management interface runs on this port
- Use
searchsploit ftpto find known exploits - Monitor traffic on port 21 with Wireshark or tcpdump for anomalies
- Ensure the service is patched to the latest version to prevent known CVE exploitation