- 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 902: self documenting Telnet Door
Port 902 is assigned by IANA to ideafarm-door (self documenting Telnet Door).
902
How ideafarm-door works
Remote accessThe client opens a session to port 902: 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
- Well-known (0-1023)
- Category
- Remote access
Is port 902 dangerous?
We have no specific security note for port 902. Its risk depends on the program actually listening on it. General advice for remote access services:
IANA registry entries for port 902
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| ideafarm-door | 902 | TCP, UDP | self documenting Telnet Door | - | - |
// source: IANA service name and port number registry
Which program uses port 902, and is it reachable?
Linux
sudo ss -ltnup 'sport = :902' # process listening on 902
sudo lsof -nP -i :902macOS
sudo lsof -nP -i :902
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 902 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 902 netstat -ano | findstr :902
From another machine
nmap -p 902 -sV <host> sudo nmap -sU -p 902 <host> nc -zv <host> 902
Block it in the firewall
sudo ufw deny 902/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 902" -Direction Inbound -LocalPort 902 -Protocol TCP -Action Block # Windows
What is port 902 used for?
Port 902 is assigned by IANA to ideafarm-door (self documenting Telnet Door).
Is port 902 TCP or UDP?
Port 902 is registered for TCP and UDP.
Is it safe to open port 902?
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 902 is open?
On Linux run "ss -ltnup 'sport = :902'", on macOS "lsof -nP -i :902", and on Windows "netstat -ano | findstr :902" to see the local process. From another machine, "nmap -p 902 <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