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// DevOps, cloud & containers

Port 4889: xcap code analysis portal cluster control and administration

Port 4889 is assigned by IANA to xcap-control (xcap code analysis portal cluster control and administration).

4889

How xcap-control works

DevOps, cloud & containers
adminhostxcap-control adminhostxcap-control

Commands sent to port 4889 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)
Category
DevOps, cloud & containers
01 Security

Is port 4889 dangerous?

We have no specific security note for port 4889. 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 4889

ServicePortTransportDescriptionReferenceUpdated
xcap-control 4889 TCP xcap code analysis portal cluster control and administration - 2018-06-06
-4889-Reserved--

// source: IANA service name and port number registry

03 Check it

Which program uses port 4889, and is it reachable?

Linux

sudo ss -ltnup 'sport = :4889'      # process listening on 4889
sudo lsof -nP -i :4889

macOS

sudo lsof -nP -i :4889

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 4889 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 4889
netstat -ano | findstr :4889

From another machine

nmap -p 4889 -sV <host>
nc -zv <host> 4889

Block it in the firewall

sudo ufw deny 4889/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 4889" -Direction Inbound -LocalPort 4889 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 4889 used for?

Port 4889 is assigned by IANA to xcap-control (xcap code analysis portal cluster control and administration).

Is port 4889 TCP or UDP?

Port 4889 is registered for TCP.

Is it safe to open port 4889?

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 4889 is open?

On Linux run "ss -ltnup 'sport = :4889'", on macOS "lsof -nP -i :4889", and on Windows "netstat -ano | findstr :4889" to see the local process. From another machine, "nmap -p 4889 <host>" shows whether it is reachable.

05 Related
:2375 Docker API (HTTP) tcp · critical risk :2376 Docker API (TLS) tcp · high risk :6443 Kubernetes API tcp · udp · high risk :10250 Kubelet API tcp · critical risk :2379 etcd tcp · critical risk :8500 Consul tcp · udp · high risk :4505 SaltStack tcp · critical risk :9000 PHP-FPM / SonarQube / Portainer tcp · udp · high risk

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