All ports
Port513/TCP
loginPort
513
Protocol
TCP
Category
Well-Known
Service
login
What is port 513?
Port 513/TCP is a Well-Known port, assigned by IANA for widely recognized services. It is associated with the login service.
remote login a la telnet; automatic authentication performed based on priviledged port numbers and distributed data bases which identify "authentication domains"
Useful commands
nmapnmap -p 513 -sV example.comnetcatnc -zv example.com 513curlcurl -v http://example.com:513/telnettelnet example.com 513bash(echo > /dev/tcp/example.com/513) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 513/tcpDeny
sudo ufw deny 513/tcpiptablesAllow
sudo iptables -A INPUT -p tcp --dport 513 -j ACCEPTDeny
sudo iptables -D INPUT -p tcp --dport 513 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=513/tcpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 513" dir=in action=allow protocol=TCP localport=513Security 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- Outdated versions with vulnerabilities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 513/TCP?
Port 513/TCP is associated with the login service. remote login a la telnet; automatic authentication performed based on priviledged port numbers and distributed data bases which identify "authentication domains"
Is it safe to expose port 513 to the Internet?
It depends on the service and configuration. Port 513 (login) 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 513 is open?
You can use nmap: `nmap -p 513 -sV example.com`, netcat: `nc -zv example.com 513`, or the bash command: `(echo > /dev/tcp/example.com/513) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 513 on my firewall?
On Linux with UFW: `sudo ufw allow 513/tcp` (open) or `sudo ufw deny 513/tcp` (close). With iptables: `sudo iptables -A INPUT -p tcp --dport 513 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 513" dir=in action=allow protocol=TCP localport=513`.
What applications and services use port 513?
Port 513/TCP is used by the login service. Specific uses depend on the software and configuration. Check our related tools section for more information.