All ports
Port4128/UDP
nufwPort
4128
Protocol
UDP
Category
Registered
Service
nufw
What is port 4128?
Port 4128/UDP is a Registered port, registered with IANA for specific applications. It is associated with the nufw service.
NuFW decision delegation protocol
Useful commands
nmapnmap -p 4128 -sV example.comnetcatnc -zv example.com 4128curlcurl -v http://example.com:4128/telnettelnet example.com 4128bash(echo > /dev/udp/example.com/4128) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 4128/udpDeny
sudo ufw deny 4128/udpiptablesAllow
sudo iptables -A INPUT -p udp --dport 4128 -j ACCEPTDeny
sudo iptables -D INPUT -p udp --dport 4128 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=4128/udpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 4128" dir=in action=allow protocol=UDP localport=4128Security 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- Outdated versions with vulnerabilities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 4128/UDP?
Port 4128/UDP is associated with the nufw service. NuFW decision delegation protocol
Is it safe to expose port 4128 to the Internet?
It depends on the service and configuration. Port 4128 (nufw) is a Registered 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 4128 is open?
You can use nmap: `nmap -p 4128 -sV example.com`, netcat: `nc -zv example.com 4128`, or the bash command: `(echo > /dev/udp/example.com/4128) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 4128 on my firewall?
On Linux with UFW: `sudo ufw allow 4128/udp` (open) or `sudo ufw deny 4128/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 4128 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 4128" dir=in action=allow protocol=UDP localport=4128`.
What applications and services use port 4128?
Port 4128/UDP is used by the nufw service. Specific uses depend on the software and configuration. Check our related tools section for more information.