← Port Encyclopedia
400
Port-400
TCP
System Low Risk
Reserved or unassigned port 400 — may appear in network scans as open, closed, or filtered

🔍 How to Scan Port 400

nmap -sV -p 400 target
nmap -sV -sC --script=banner -p 400 target
nc -zv target 400

🛡️ Security Considerations

  • Scan port 400 with nmap -sV to identify the exact service and version
  • If Port-400 is not needed, close or firewall this port immediately
  • Check for default credentials if a management interface runs on this port
  • Use searchsploit port-400 to find known exploits
  • Monitor traffic on port 400 with Wireshark or tcpdump for anomalies
  • Ensure the service is patched to the latest version to prevent known CVE exploitation