CyberHunter
// Remote access

Port 3897: Simple Distributed Objects over SSH

Port 3897 is assigned by IANA to sdo-ssh (Simple Distributed Objects over SSH).

3897

How sdo-ssh works

Remote access
terminal:3897sdo-ssh terminal:3897sdo-ssh

The client opens a session to port 3897: 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)
01 Security

Is port 3897 dangerous?

We have no specific security note for port 3897. Its risk depends on the program actually listening on it. General advice for remote access services:

  • 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.
02 Registry

IANA registry entries for port 3897

ServicePortTransportDescriptionReferenceUpdated
sdo-ssh 3897 TCP, UDP Simple Distributed Objects over SSH - 2003-10

// source: IANA service name and port number registry

03 Check it

Which program uses port 3897, and is it reachable?

Linux

sudo ss -ltnup 'sport = :3897'      # process listening on 3897
sudo lsof -nP -i :3897

macOS

sudo lsof -nP -i :3897

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 3897 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 3897
netstat -ano | findstr :3897

From another machine

nmap -p 3897 -sV <host>
sudo nmap -sU -p 3897 <host>
nc -zv <host> 3897

Block it in the firewall

sudo ufw deny 3897/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 3897" -Direction Inbound -LocalPort 3897 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 3897 used for?

Port 3897 is assigned by IANA to sdo-ssh (Simple Distributed Objects over SSH).

Is port 3897 TCP or UDP?

Port 3897 is registered for TCP and UDP.

Is it safe to open port 3897?

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 3897 is open?

On Linux run "ss -ltnup 'sport = :3897'", on macOS "lsof -nP -i :3897", and on Windows "netstat -ano | findstr :3897" to see the local process. From another machine, "nmap -p 3897 <host>" shows whether it is reachable.

05 Related