All ports
Port55/TCP
isi-glPort
55
Protocol
TCP
Category
Well-Known
Service
isi-gl
What is port 55?
Port 55/TCP is a Well-Known port, assigned by IANA for widely recognized services. It is associated with the isi-gl service.
ISI Graphics Language
Useful commands
nmapnmap -p 55 -sV example.comnetcatnc -zv example.com 55curlcurl -v http://example.com:55/telnettelnet example.com 55bash(echo > /dev/tcp/example.com/55) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 55/tcpDeny
sudo ufw deny 55/tcpiptablesAllow
sudo iptables -A INPUT -p tcp --dport 55 -j ACCEPTDeny
sudo iptables -D INPUT -p tcp --dport 55 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=55/tcpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 55" dir=in action=allow protocol=TCP localport=55Security 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- Outdated versions with vulnerabilities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 55/TCP?
Port 55/TCP is associated with the isi-gl service. ISI Graphics Language
Is it safe to expose port 55 to the Internet?
It depends on the service and configuration. Port 55 (isi-gl) 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 55 is open?
You can use nmap: `nmap -p 55 -sV example.com`, netcat: `nc -zv example.com 55`, or the bash command: `(echo > /dev/tcp/example.com/55) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 55 on my firewall?
On Linux with UFW: `sudo ufw allow 55/tcp` (open) or `sudo ufw deny 55/tcp` (close). With iptables: `sudo iptables -A INPUT -p tcp --dport 55 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 55" dir=in action=allow protocol=TCP localport=55`.
What applications and services use port 55?
Port 55/TCP is used by the isi-gl service. Specific uses depend on the software and configuration. Check our related tools section for more information.