← Port Encyclopedia
851
Port-851
TCP
System Low Risk
Reserved or unassigned port 851 — may appear in network scans as open, closed, or filtered

🔍 How to Scan Port 851

nmap -sV -p 851 target
nmap -sV -sC --script=banner -p 851 target
nc -zv target 851

🛡️ Security Considerations

  • Scan port 851 with nmap -sV to identify the exact service and version
  • If Port-851 is not needed, close or firewall this port immediately
  • Check for default credentials if a management interface runs on this port
  • Use searchsploit port-851 to find known exploits
  • Monitor traffic on port 851 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 846
Port-846
Port 847
Port-847
Port 848
Port-848
Port 849
Port-849
Port 850
Port-850
Port 852
Port-852
Port 853
Port-853
Port 854
Port-854
Port 855
Port-855
Port 856
Port-856
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