← Port Encyclopedia
303
Port-303
TCP
System Low Risk
Reserved or unassigned port 303 — may appear in network scans as open, closed, or filtered

🔍 How to Scan Port 303

nmap -sV -p 303 target
nmap -sV -sC --script=banner -p 303 target
nc -zv target 303

🛡️ Security Considerations

  • Scan port 303 with nmap -sV to identify the exact service and version
  • If Port-303 is not needed, close or firewall this port immediately
  • Check for default credentials if a management interface runs on this port
  • Use searchsploit port-303 to find known exploits
  • Monitor traffic on port 303 with Wireshark or tcpdump for anomalies
  • Ensure the service is patched to the latest version to prevent known CVE exploitation

🔗 Related System Ports

Port 1
TCPMUX
Port 5
RJE
Port 7
Echo
Port 9
Discard
Port 11
systat
Port 13
Daytime
Port 17
QOTD
Port 19
Chargen
Port 37
Time
Port 79
Finger
Port 111
RPCbind
Port 113
Ident

📍 Nearby Ports

Port 298
Port-298
Port 299
Port-299
Port 300
Port-300
Port 301
Port-301
Port 302
Port-302
Port 304
Port-304
Port 305
Port-305
Port 306
Port-306
Port 307
Port-307
Port 308
Port-308
📚 Learn Network Scanning — Free Course