All ports

Port1983/UDP

lhtp

Port

1983

Protocol

UDP

Category

Registered

Service

lhtp

What is port 1983?

Port 1983/UDP is a Registered port, registered with IANA for specific applications. It is associated with the lhtp service.

Loophole Test Protocol

Useful commands

nmapnmap -p 1983 -sV example.com
netcatnc -zv example.com 1983
curlcurl -v http://example.com:1983/
telnettelnet example.com 1983
bash(echo > /dev/udp/example.com/1983) 2>/dev/null

Firewall commands

UFWAllow
sudo ufw allow 1983/udp
Deny
sudo ufw deny 1983/udp
iptablesAllow
sudo iptables -A INPUT -p udp --dport 1983 -j ACCEPT
Deny
sudo iptables -D INPUT -p udp --dport 1983 -j ACCEPT
firewalldAllow
sudo firewall-cmd --permanent --add-port=1983/udp
WindowsAllow
netsh advfirewall firewall add rule name="Open Port 1983" dir=in action=allow protocol=UDP localport=1983

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  • Outdated versions with vulnerabilities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 1983/UDP?

Port 1983/UDP is associated with the lhtp service. Loophole Test Protocol

Is it safe to expose port 1983 to the Internet?

It depends on the service and configuration. Port 1983 (lhtp) 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 1983 is open?

You can use nmap: `nmap -p 1983 -sV example.com`, netcat: `nc -zv example.com 1983`, or the bash command: `(echo > /dev/udp/example.com/1983) 2>/dev/null && echo "Open" || echo "Closed"`.

How do I open or close port 1983 on my firewall?

On Linux with UFW: `sudo ufw allow 1983/udp` (open) or `sudo ufw deny 1983/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 1983 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 1983" dir=in action=allow protocol=UDP localport=1983`.

What applications and services use port 1983?

Port 1983/UDP is used by the lhtp service. Specific uses depend on the software and configuration. Check our related tools section for more information.