Should port 5901 be open on my firewall?

Port 5901 should only be open with strict firewall rules whitelisting trusted IP addresses. Enable rate limiting and intrusion detection systems.

What transport protocol does port 5901 use?

Port 5901 (VNC Display 1) uses the TCP transport protocol and falls under the Remote Access category.

:5901 (TCP)

VNC Display 1

Q: Is port 5901 (VNC Display 1) dangerous?

Port 5901 is classified as high risk. It is a common target for automated scanning and brute-force attacks. Restrict access to trusted IPs if exposure is necessary.

High Risk

TCP — Remote Access

Port Overview

Port Number 5901

Service Name VNC Display 1

Transport Protocol TCP

Category Remote Access

Security Risk High

Port Range Registered (1024-49151)

What is Port 5901?

Port 5901 is used by VNC (Virtual Network Computing) for the second virtual display (display :1). VNC servers increment the port number by display number, so display :0 uses 5900, display :1 uses 5901, and so on. This convention is used when running multiple VNC sessions simultaneously on the same server.

TCP Remote Access Commonly Used

Security Considerations

Port 5901 (VNC Display 1) is classified as high risk. This port is a common target for automated scanning and brute-force attacks. If you must expose it, restrict access to known IP addresses.

Recommendation: Use firewall rules to whitelist trusted IPs. Enable rate limiting and intrusion detection.

Related Ports — Remote Access

22 SSH 23 Telnet 57 Private Terminal Access 89 SU/MIT Telnet Gateway 95 SUPDUP 107 Remote Telnet 177 XDMCP 219 Uarps

Related Terms

SSL/TLS Certificate DDoS DNS Spoofing Encryption Firewall HTTPS