- 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 169: SEND
Port 169 is assigned by IANA to send (SEND).
How send works
Other servicesThe client sends a request to port 169 and the send 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
- Well-known (0-1023)
- Category
- Other services
Is port 169 dangerous?
We have no specific security note for port 169. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 169
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| send | 169 | TCP, UDP | SEND | - | 2019-04-22 |
// source: IANA service name and port number registry
Which program uses port 169, and is it reachable?
Linux
sudo ss -ltnup 'sport = :169' # process listening on 169
sudo lsof -nP -i :169macOS
sudo lsof -nP -i :169
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 169 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 169 netstat -ano | findstr :169
From another machine
nmap -p 169 -sV <host> sudo nmap -sU -p 169 <host> nc -zv <host> 169
Block it in the firewall
sudo ufw deny 169/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 169" -Direction Inbound -LocalPort 169 -Protocol TCP -Action Block # Windows
What is port 169 used for?
Port 169 is assigned by IANA to send (SEND).
Is port 169 TCP or UDP?
Port 169 is registered for TCP and UDP.
Is it safe to open port 169?
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 169 is open?
On Linux run "ss -ltnup 'sport = :169'", on macOS "lsof -nP -i :169", and on Windows "netstat -ano | findstr :169" to see the local process. From another machine, "nmap -p 169 <host>" shows whether it is reachable.