All ports

Port3971/UDP

lanrevserver

Port

3971

Protocol

UDP

Category

Registered

Service

lanrevserver

What is port 3971?

Port 3971/UDP is a Registered port, registered with IANA for specific applications. It is associated with the lanrevserver service.

LANrev Server

Useful commands

nmapnmap -p 3971 -sV example.com
netcatnc -zv example.com 3971
curlcurl -v http://example.com:3971/
telnettelnet example.com 3971
bash(echo > /dev/udp/example.com/3971) 2>/dev/null

Firewall commands

UFWAllow
sudo ufw allow 3971/udp
Deny
sudo ufw deny 3971/udp
iptablesAllow
sudo iptables -A INPUT -p udp --dport 3971 -j ACCEPT
Deny
sudo iptables -D INPUT -p udp --dport 3971 -j ACCEPT
firewalldAllow
sudo firewall-cmd --permanent --add-port=3971/udp
WindowsAllow
netsh advfirewall firewall add rule name="Open Port 3971" dir=in action=allow protocol=UDP localport=3971

Security 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  • Outdated versions with vulnerabilities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 3971/UDP?

Port 3971/UDP is associated with the lanrevserver service. LANrev Server

Is it safe to expose port 3971 to the Internet?

It depends on the service and configuration. Port 3971 (lanrevserver) 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 3971 is open?

You can use nmap: `nmap -p 3971 -sV example.com`, netcat: `nc -zv example.com 3971`, or the bash command: `(echo > /dev/udp/example.com/3971) 2>/dev/null && echo "Open" || echo "Closed"`.

How do I open or close port 3971 on my firewall?

On Linux with UFW: `sudo ufw allow 3971/udp` (open) or `sudo ufw deny 3971/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 3971 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 3971" dir=in action=allow protocol=UDP localport=3971`.

What applications and services use port 3971?

Port 3971/UDP is used by the lanrevserver service. Specific uses depend on the software and configuration. Check our related tools section for more information.