CyberHunter
// Directory & authentication

Port 1151: Unizensus Login Server

Port 1151 is assigned by IANA to unizensus (Unizensus Login Server).

1151

How unizensus works

Directory & authentication
userdirectoryunizensusresponse userdirectoryunizensusresponse

The client proves who it is on port 1151 and gets an answer (or a ticket) it can use with other services.

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)
01 Security

Is port 1151 dangerous?

We have no specific security note for port 1151. Its risk depends on the program actually listening on it. General advice for directory & authentication services:

  • Keep directory and authentication services on internal networks.
  • Require signing or TLS and disable anonymous queries.
  • Monitor authentication failures for spraying and brute force.
02 Registry

IANA registry entries for port 1151

ServicePortTransportDescriptionReferenceUpdated
unizensus 1151 TCP, UDP Unizensus Login Server - 2005-11

// source: IANA service name and port number registry

03 Check it

Which program uses port 1151, and is it reachable?

Linux

sudo ss -ltnup 'sport = :1151'      # process listening on 1151
sudo lsof -nP -i :1151

macOS

sudo lsof -nP -i :1151

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 1151 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 1151
netstat -ano | findstr :1151

From another machine

nmap -p 1151 -sV <host>
sudo nmap -sU -p 1151 <host>
nc -zv <host> 1151

Block it in the firewall

sudo ufw deny 1151/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 1151" -Direction Inbound -LocalPort 1151 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 1151 used for?

Port 1151 is assigned by IANA to unizensus (Unizensus Login Server).

Is port 1151 TCP or UDP?

Port 1151 is registered for TCP and UDP.

Is it safe to open port 1151?

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. Keep directory and authentication services on internal networks.

How do I check if port 1151 is open?

On Linux run "ss -ltnup 'sport = :1151'", on macOS "lsof -nP -i :1151", and on Windows "netstat -ano | findstr :1151" to see the local process. From another machine, "nmap -p 1151 <host>" shows whether it is reachable.

05 Related