- Close the port if nothing on the host needs it.
- Identify the process that listens on it (commands below) before opening it in a firewall.
- Expose a service only to the networks that use it.
Port 4390: Physical Access Control
Port 4390 is assigned by IANA to wiegand (Physical Access Control).
How wiegand works
Other servicesThe client sends a request to port 4390 and the wiegand service answers.
- Transport
- TCP · UDP
- Exposure risk
- not rated depends on the program listening
- Encryption
- Unknownnot stated by the registry
- IANA status
- Assigned1 registered service
- Range
- Registered (1024-49151)
- Category
- Other services
Is port 4390 dangerous?
We have no specific security note for port 4390. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 4390
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| wiegand | 4390 | TCP, UDP | Physical Access Control | - | 2008-08-25 |
// source: IANA service name and port number registry
Which program uses port 4390, and is it reachable?
Linux
sudo ss -ltnup 'sport = :4390' # process listening on 4390
sudo lsof -nP -i :4390macOS
sudo lsof -nP -i :4390
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 4390 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 4390 netstat -ano | findstr :4390
From another machine
nmap -p 4390 -sV <host> sudo nmap -sU -p 4390 <host> nc -zv <host> 4390
Block it in the firewall
sudo ufw deny 4390/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 4390" -Direction Inbound -LocalPort 4390 -Protocol TCP -Action Block # Windows
What is port 4390 used for?
Port 4390 is assigned by IANA to wiegand (Physical Access Control).
Is port 4390 TCP or UDP?
Port 4390 is registered for TCP and UDP.
Is it safe to open port 4390?
It depends on the program that listens on it. Open it only for a service you know and only to the networks that need it. Close the port if nothing on the host needs it.
How do I check if port 4390 is open?
On Linux run "ss -ltnup 'sport = :4390'", on macOS "lsof -nP -i :4390", and on Windows "netstat -ano | findstr :4390" to see the local process. From another machine, "nmap -p 4390 <host>" shows whether it is reachable.