All ports
Port4739/UDP
ipfixPort
4739
Protocol
UDP
Category
Registered
Service
ipfix
What is port 4739?
Port 4739/UDP is a Registered port, registered with IANA for specific applications. It is associated with the ipfix service.
IP Flow Info Export
Useful commands
nmapnmap -p 4739 -sV example.comnetcatnc -zv example.com 4739curlcurl -v http://example.com:4739/telnettelnet example.com 4739bash(echo > /dev/udp/example.com/4739) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 4739/udpDeny
sudo ufw deny 4739/udpiptablesAllow
sudo iptables -A INPUT -p udp --dport 4739 -j ACCEPTDeny
sudo iptables -D INPUT -p udp --dport 4739 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=4739/udpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 4739" dir=in action=allow protocol=UDP localport=4739Security 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- Outdated versions with vulnerabilities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 4739/UDP?
Port 4739/UDP is associated with the ipfix service. IP Flow Info Export
Is it safe to expose port 4739 to the Internet?
It depends on the service and configuration. Port 4739 (ipfix) 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 4739 is open?
You can use nmap: `nmap -p 4739 -sV example.com`, netcat: `nc -zv example.com 4739`, or the bash command: `(echo > /dev/udp/example.com/4739) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 4739 on my firewall?
On Linux with UFW: `sudo ufw allow 4739/udp` (open) or `sudo ufw deny 4739/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 4739 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 4739" dir=in action=allow protocol=UDP localport=4739`.
What applications and services use port 4739?
Port 4739/UDP is used by the ipfix service. Specific uses depend on the software and configuration. Check our related tools section for more information.