CyberHunter
LinkedIn profile - Bastien Cordier Email: contact@bastiencordier.pro
// Other services

Port 4441: Netblox Protocol

Port 4441 is assigned by IANA to netblox (Netblox Protocol).

4441

How netblox works

Other services
client:4441netbloxresponse client:4441netbloxresponse

The client sends a request to port 4441 and the netblox service answers.

Transport
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
Other services
01 Security

Is port 4441 dangerous?

We have no specific security note for port 4441. Its risk depends on the program actually listening on it. General advice for other services services:

  • 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.
02 Registry

IANA registry entries for port 4441

ServicePortTransportDescriptionReferenceUpdated
netblox 4441 UDP Netblox Protocol - 2008-07-10
-4441-Reserved--

// source: IANA service name and port number registry

03 Check it

Which program uses port 4441, and is it reachable?

Linux

sudo ss -ltnup 'sport = :4441'      # process listening on 4441
sudo lsof -nP -i :4441

macOS

sudo lsof -nP -i :4441

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 4441 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 4441
netstat -ano | findstr :4441

From another machine

nmap -p 4441 -sV <host>
sudo nmap -sU -p 4441 <host>
nc -zv <host> 4441

Block it in the firewall

sudo ufw deny 4441/udp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 4441" -Direction Inbound -LocalPort 4441 -Protocol UDP -Action Block  # Windows
04 FAQ
What is port 4441 used for?

Port 4441 is assigned by IANA to netblox (Netblox Protocol).

Is port 4441 TCP or UDP?

Port 4441 is registered for UDP.

Is it safe to open port 4441?

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 4441 is open?

On Linux run "ss -ltnup 'sport = :4441'", on macOS "lsof -nP -i :4441", and on Windows "netstat -ano | findstr :4441" to see the local process. From another machine, "nmap -p 4441 <host>" shows whether it is reachable.

05 Related
: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

Latest vulnerability news

All news