Port 445 is used by Server Message Block (SMB). Windows file sharing and network printing. Used by Windows to share drives, folders, and printers on local networks.
What Does an Open Port 445 Mean?
Windows file sharing is exposed. Port 445 should NEVER be open to the internet. It was the primary attack vector for the WannaCry ransomware (2017) which infected 200,000+ machines globally.
This port should NOT be open to the public internet on typical systems. If you see it open, investigate immediately.
Security Risk Level
Critical Risk
How to Check if Port 445 Is Open
Use the ExamineIP Port Scanner to check if port 445 is open on any IP address from the public internet. Enter the target IP and select the relevant port preset.
How to Close Port 445
- Stop the service using port 445 if you no longer need it
- Add a firewall rule blocking inbound connections on port 445
- Check your router for port forwarding rules that expose this port
- Run
netstat -ano | findstr :445(Windows) to see which process is using it
Related Ports
SMB is related to: {implode(‘, ‘, Array)}
Protect Your Open Ports
If you need services like remote access, use a VPN to create a private encrypted tunnel instead of exposing ports directly to the internet. A VPN also hides your real IP address so port scanners cannot identify your device. Try PureVPN or IPVanish.