All ports

Port56/TCP

xns-auth

Port

56

Protocol

TCP

Category

Well-Known

Service

xns-auth

What is port 56?

Port 56/TCP is a Well-Known port, assigned by IANA for widely recognized services. It is associated with the xns-auth service.

XNS Authentication

Useful commands

nmapnmap -p 56 -sV example.com
netcatnc -zv example.com 56
curlcurl -v http://example.com:56/
telnettelnet example.com 56
bash(echo > /dev/tcp/example.com/56) 2>/dev/null

Firewall commands

UFWAllow
sudo ufw allow 56/tcp
Deny
sudo ufw deny 56/tcp
iptablesAllow
sudo iptables -A INPUT -p tcp --dport 56 -j ACCEPT
Deny
sudo iptables -D INPUT -p tcp --dport 56 -j ACCEPT
firewalldAllow
sudo firewall-cmd --permanent --add-port=56/tcp
WindowsAllow
netsh advfirewall firewall add rule name="Open Port 56" dir=in action=allow protocol=TCP localport=56

Security Risks

  • Unauthorized access to the service
  • Data exposure if the service is unauthenticated
  • Outdated versions with vulnerabilities
  • Incorrect service configuration

Frequently Asked Questions

What service runs on port 56/TCP?

Port 56/TCP is associated with the xns-auth service. XNS Authentication

Is it safe to expose port 56 to the Internet?

It depends on the service and configuration. Port 56 (xns-auth) is a Well-Known port. If you need to expose it, keep the service updated, use strong authentication, and configure a firewall. It's always recommended to restrict access by IP when possible.

How do I check if port 56 is open?

You can use nmap: `nmap -p 56 -sV example.com`, netcat: `nc -zv example.com 56`, or the bash command: `(echo > /dev/tcp/example.com/56) 2>/dev/null && echo "Open" || echo "Closed"`.

How do I open or close port 56 on my firewall?

On Linux with UFW: `sudo ufw allow 56/tcp` (open) or `sudo ufw deny 56/tcp` (close). With iptables: `sudo iptables -A INPUT -p tcp --dport 56 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 56" dir=in action=allow protocol=TCP localport=56`.

What applications and services use port 56?

Port 56/TCP is used by the xns-auth service. Specific uses depend on the software and configuration. Check our related tools section for more information.

Related ports