← Port Encyclopedia
81
HTTP-Alt
TCP
Web High Risk
Alternative HTTP — often used for web admin panels and secondary web services

🔍 How to Scan Port 81

nmap -sV -p 81 target
nmap -sV -sC --script=banner -p 81 target
nc -zv target 81

🛡️ Security Considerations

  • Scan port 81 with nmap -sV to identify the exact service and version
  • If HTTP-Alt is not needed, close or firewall this port immediately
  • Check for default credentials if a management interface runs on this port
  • Use searchsploit http-alt to find known exploits
  • Monitor traffic on port 81 with Wireshark or tcpdump for anomalies
  • Ensure the service is patched to the latest version to prevent known CVE exploitation