Port 3389: RDP
Windows Remote Desktop.
- Port
- 3389
- Protocol
- TCP
- Service
- RDP
- Exposure
- Do not expose to the internet
What is port 3389 used for?
Remote administration of Windows machines.
Is it safe to expose port 3389 to the internet?
One of the most attacked ports on the internet. Put it behind a VPN or a gateway with multi-factor authentication.
If port 3389 seems closed or unreachable
- Check that the RDP service is running and listening on port 3389, not only on 127.0.0.1.
- Check the firewall on the host itself (Windows Defender Firewall, iptables, nftables, ufw) for a rule that allows TCP 3389.
- If the host is behind a router, confirm the forwarding rule points to the correct internal address and that your internet provider does not use carrier-grade NAT.
- Test from outside your own network. A port can be open locally and blocked at the edge, or the other way round.
Using port 3389 safely
Treat port 3389 as an internal-only service. Reach it through a VPN or an SSH tunnel, restrict it by source address, and keep the software that listens on it patched.
Check whether port 3389 is open on your host
The check connects from our server, so it shows what the internet can reach.
Open the port checker