← Port Encyclopedia
657
Port-657
TCP
System Low Risk
Reserved or unassigned port 657 — may appear in network scans as open, closed, or filtered

🔍 How to Scan Port 657

nmap -sV -p 657 target
nmap -sV -sC --script=banner -p 657 target
nc -zv target 657

🛡️ Security Considerations

  • Scan port 657 with nmap -sV to identify the exact service and version
  • If Port-657 is not needed, close or firewall this port immediately
  • Check for default credentials if a management interface runs on this port
  • Use searchsploit port-657 to find known exploits
  • Monitor traffic on port 657 with Wireshark or tcpdump for anomalies
  • Ensure the service is patched to the latest version to prevent known CVE exploitation

🔗 Related System Ports

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systat
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📍 Nearby Ports

Port 652
Port-652
Port 653
Port-653
Port 654
Port-654
Port 655
Port-655
Port 656
Port-656
Port 658
Port-658
Port 659
Port-659
Port 660
Port-660
Port 661
Port-661
Port 662
Port-662
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