- Close the port if nothing on the host needs it.
- Identify the process that listens on it (commands below) before opening it in a firewall.
- Expose a service only to the networks that use it.
Port 1321: PIP
Port 1321 is assigned by IANA to pip (PIP).
How pip works
Other servicesThe client sends a request to port 1321 and the pip service answers.
- 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)
- Category
- Other services
Is port 1321 dangerous?
We have no specific security note for port 1321. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 1321
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| pip | 1321 | TCP, UDP | PIP | - | - |
// source: IANA service name and port number registry
Which program uses port 1321, and is it reachable?
Linux
sudo ss -ltnup 'sport = :1321' # process listening on 1321
sudo lsof -nP -i :1321macOS
sudo lsof -nP -i :1321
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 1321 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 1321 netstat -ano | findstr :1321
From another machine
nmap -p 1321 -sV <host> sudo nmap -sU -p 1321 <host> nc -zv <host> 1321
Block it in the firewall
sudo ufw deny 1321/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 1321" -Direction Inbound -LocalPort 1321 -Protocol TCP -Action Block # Windows
What is port 1321 used for?
Port 1321 is assigned by IANA to pip (PIP).
Is port 1321 TCP or UDP?
Port 1321 is registered for TCP and UDP.
Is it safe to open port 1321?
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. Close the port if nothing on the host needs it.
How do I check if port 1321 is open?
On Linux run "ss -ltnup 'sport = :1321'", on macOS "lsof -nP -i :1321", and on Windows "netstat -ano | findstr :1321" to see the local process. From another machine, "nmap -p 1321 <host>" shows whether it is reachable.