All ports
Port518/TCP
ntalkPort
518
Protocol
TCP
Category
Well-Known
Service
ntalk
What is port 518?
Port 518/TCP is a Well-Known port, assigned by IANA for widely recognized services. It is associated with the ntalk service.
Useful commands
nmapnmap -p 518 -sV example.comnetcatnc -zv example.com 518curlcurl -v http://example.com:518/telnettelnet example.com 518bash(echo > /dev/tcp/example.com/518) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 518/tcpDeny
sudo ufw deny 518/tcpiptablesAllow
sudo iptables -A INPUT -p tcp --dport 518 -j ACCEPTDeny
sudo iptables -D INPUT -p tcp --dport 518 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=518/tcpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 518" dir=in action=allow protocol=TCP localport=518Security 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- Outdated versions with vulnerabilities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 518/TCP?
Port 518/TCP is associated with the ntalk service. No detailed description is available in the IANA registry.
Is it safe to expose port 518 to the Internet?
It depends on the service and configuration. Port 518 (ntalk) 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 518 is open?
You can use nmap: `nmap -p 518 -sV example.com`, netcat: `nc -zv example.com 518`, or the bash command: `(echo > /dev/tcp/example.com/518) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 518 on my firewall?
On Linux with UFW: `sudo ufw allow 518/tcp` (open) or `sudo ufw deny 518/tcp` (close). With iptables: `sudo iptables -A INPUT -p tcp --dport 518 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 518" dir=in action=allow protocol=TCP localport=518`.
What applications and services use port 518?
Port 518/TCP is used by the ntalk service. Specific uses depend on the software and configuration. Check our related tools section for more information.