CyberHunter
// DevOps, cloud & containers

Port 4421: Multi-Platform Remote Management for Cloud Infrastructure

Port 4421 is assigned by IANA to scaleft (Multi-Platform Remote Management for Cloud Infrastructure).

4421

How scaleft works

DevOps, cloud & containers
adminhostscaleft adminhostscaleft

Commands sent to port 4421 create and control containers or cluster resources on the host.

Transport
TCP
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 4421 dangerous?

We have no specific security note for port 4421. Its risk depends on the program actually listening on it. General advice for devops, cloud & containers services:

  • Container and orchestration APIs give full control of hosts: require mutual TLS and RBAC.
  • Never expose them to the Internet.
  • Rotate tokens and certificates and audit who has access.
02 Registry

IANA registry entries for port 4421

ServicePortTransportDescriptionReferenceUpdated
scaleft 4421 TCP Multi-Platform Remote Management for Cloud Infrastructure - 2016-04-07
-4421-Reserved--

// source: IANA service name and port number registry

03 Check it

Which program uses port 4421, and is it reachable?

Linux

sudo ss -ltnup 'sport = :4421'      # process listening on 4421
sudo lsof -nP -i :4421

macOS

sudo lsof -nP -i :4421

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 4421 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 4421
netstat -ano | findstr :4421

From another machine

nmap -p 4421 -sV <host>
nc -zv <host> 4421

Block it in the firewall

sudo ufw deny 4421/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 4421" -Direction Inbound -LocalPort 4421 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 4421 used for?

Port 4421 is assigned by IANA to scaleft (Multi-Platform Remote Management for Cloud Infrastructure).

Is port 4421 TCP or UDP?

Port 4421 is registered for TCP.

Is it safe to open port 4421?

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. Container and orchestration APIs give full control of hosts: require mutual TLS and RBAC.

How do I check if port 4421 is open?

On Linux run "ss -ltnup 'sport = :4421'", on macOS "lsof -nP -i :4421", and on Windows "netstat -ano | findstr :4421" to see the local process. From another machine, "nmap -p 4421 <host>" shows whether it is reachable.

05 Related