5901
VNC Display 1
High RiskTCP — 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.