- 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 155: NETSC
Port 155 is assigned by IANA to netsc-dev (NETSC).
155
How netsc-dev works
Other servicesThe client sends a request to port 155 and the netsc-dev 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 155 dangerous?
We have no specific security note for port 155. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 155
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| netsc-dev | 155 | TCP, UDP | NETSC | - | - |
// source: IANA service name and port number registry
Which program uses port 155, and is it reachable?
Linux
sudo ss -ltnup 'sport = :155' # process listening on 155
sudo lsof -nP -i :155macOS
sudo lsof -nP -i :155
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 155 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 155 netstat -ano | findstr :155
From another machine
nmap -p 155 -sV <host> sudo nmap -sU -p 155 <host> nc -zv <host> 155
Block it in the firewall
sudo ufw deny 155/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 155" -Direction Inbound -LocalPort 155 -Protocol TCP -Action Block # Windows
What is port 155 used for?
Port 155 is assigned by IANA to netsc-dev (NETSC).
Is port 155 TCP or UDP?
Port 155 is registered for TCP and UDP.
Is it safe to open port 155?
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 155 is open?
On Linux run "ss -ltnup 'sport = :155'", on macOS "lsof -nP -i :155", and on Windows "netstat -ano | findstr :155" to see the local process. From another machine, "nmap -p 155 <host>" shows whether it is reachable.
Other other services ports
:4444 Metasploit default / krb524 tcp · udp · high risk :31337 Back Orifice / elite tcp · udp · high risk :1 TCP Port Service Multiplexer tcp · udp :5 Remote Job Entry tcp · udp :9 Discard tcp · udp · sctp · dccp :11 Active Users tcp · udp :17 Quote of the Day tcp · udp :18 Message Send Protocol (historic) tcp · udp