CyberHunter
// IoT & industrial (ICS)

Port 3947: Connect and Control Protocol for Consumer, Commercial, and Industrial Electronic Devices

Port 3947 is assigned by IANA to ccp (Connect and Control Protocol for Consumer, Commercial, and Industrial Electronic Devices).

3947

How ccp works

IoT & industrial (ICS)
controllerPLCccpno authentication controllerPLCccpno authentication

A controller sends commands to an industrial device on port 3947, which acts on the physical process.

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 3947 dangerous?

We have no specific security note for port 3947. Its risk depends on the program actually listening on it. General advice for iot & industrial (ics) services:

  • Industrial and IoT protocols often have no authentication: never expose them to the Internet.
  • Segment OT networks from IT and use protocol-aware firewalls.
  • Monitor with an ICS-aware intrusion detection system.
02 Registry

IANA registry entries for port 3947

ServicePortTransportDescriptionReferenceUpdated
ccp 3947 TCP, UDP Connect and Control Protocol for Consumer, Commercial, and Industrial Electronic Devices - 2004-06

// source: IANA service name and port number registry

03 Check it

Which program uses port 3947, and is it reachable?

Linux

sudo ss -ltnup 'sport = :3947'      # process listening on 3947
sudo lsof -nP -i :3947

macOS

sudo lsof -nP -i :3947

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 3947 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 3947
netstat -ano | findstr :3947

From another machine

nmap -p 3947 -sV <host>
sudo nmap -sU -p 3947 <host>
nc -zv <host> 3947

Block it in the firewall

sudo ufw deny 3947/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 3947" -Direction Inbound -LocalPort 3947 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 3947 used for?

Port 3947 is assigned by IANA to ccp (Connect and Control Protocol for Consumer, Commercial, and Industrial Electronic Devices).

Is port 3947 TCP or UDP?

Port 3947 is registered for TCP and UDP.

Is it safe to open port 3947?

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. Industrial and IoT protocols often have no authentication: never expose them to the Internet.

How do I check if port 3947 is open?

On Linux run "ss -ltnup 'sport = :3947'", on macOS "lsof -nP -i :3947", and on Windows "netstat -ano | findstr :3947" to see the local process. From another machine, "nmap -p 3947 <host>" shows whether it is reachable.

05 Related