- Do not expose remote administration directly: use a VPN or a zero-trust access proxy.
- Require MFA or key-based authentication and lock out brute-force attempts.
- Log every login and alert on new source addresses.
Port 9555: Trispen Secure Remote Access
Port 9555 is assigned by IANA to trispen-sra (Trispen Secure Remote Access).
9555
How trispen-sra works
Remote accessThe client opens a session to port 9555: each command typed is sent to the server, which runs it and returns the output.
- 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
- Remote access
Is port 9555 dangerous?
We have no specific security note for port 9555. Its risk depends on the program actually listening on it. General advice for remote access services:
IANA registry entries for port 9555
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| trispen-sra | 9555 | TCP, UDP | Trispen Secure Remote Access | - | 2004-11 |
// source: IANA service name and port number registry
Which program uses port 9555, and is it reachable?
Linux
sudo ss -ltnup 'sport = :9555' # process listening on 9555
sudo lsof -nP -i :9555macOS
sudo lsof -nP -i :9555
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 9555 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 9555 netstat -ano | findstr :9555
From another machine
nmap -p 9555 -sV <host> sudo nmap -sU -p 9555 <host> nc -zv <host> 9555
Block it in the firewall
sudo ufw deny 9555/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 9555" -Direction Inbound -LocalPort 9555 -Protocol TCP -Action Block # Windows
What is port 9555 used for?
Port 9555 is assigned by IANA to trispen-sra (Trispen Secure Remote Access).
Is port 9555 TCP or UDP?
Port 9555 is registered for TCP and UDP.
Is it safe to open port 9555?
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. Do not expose remote administration directly: use a VPN or a zero-trust access proxy.
How do I check if port 9555 is open?
On Linux run "ss -ltnup 'sport = :9555'", on macOS "lsof -nP -i :9555", and on Windows "netstat -ano | findstr :9555" to see the local process. From another machine, "nmap -p 9555 <host>" shows whether it is reachable.
Other remote access ports
:22 SSH tcp · udp · sctp · moderate risk :3389 RDP tcp · udp · critical risk :23 Telnet tcp · udp · critical risk :5900 VNC tcp · udp · critical risk :5985 WinRM (HTTP) tcp · udp · high risk :5986 WinRM (HTTPS) tcp · udp · high risk :10000 Webmin tcp · udp · high risk :89 SU/MIT Telnet Gateway tcp · udp