← Port Encyclopedia
399
Port-399
TCP
System Low Risk
Reserved or unassigned port 399 — may appear in network scans as open, closed, or filtered

🔍 How to Scan Port 399

nmap -sV -p 399 target
nmap -sV -sC --script=banner -p 399 target
nc -zv target 399

🛡️ Security Considerations

  • Scan port 399 with nmap -sV to identify the exact service and version
  • If Port-399 is not needed, close or firewall this port immediately
  • Check for default credentials if a management interface runs on this port
  • Use searchsploit port-399 to find known exploits
  • Monitor traffic on port 399 with Wireshark or tcpdump for anomalies
  • Ensure the service is patched to the latest version to prevent known CVE exploitation

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📍 Nearby Ports

Port 394
Port-394
Port 395
Port-395
Port 396
Port-396
Port 397
Port-397
Port 398
Port-398
Port 400
Port-400
Port 401
Port-401
Port 402
Port-402
Port 403
Port-403
Port 404
Port-404
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