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Port 4553 (icshostsvc)

IANA assigns port 4553 to icshostsvc: ICS host services.

Registered (user) port, 1024-49151 TCP

IANA assignment

Service nameProtoDescriptionAssigneeReference
icshostsvc TCP ICS host services Gordan Vosicki -

Registry dates for this port: registered 2009-09-23.

Check what is listening on port 4553

Linux: is anything listening on TCP 4553?
sudo ss -tlnp 'sport = :4553'
Linux / macOS: which process owns the port
sudo lsof -nP -i :4553
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':4553 '
Windows (Command Prompt)
netstat -ano | findstr :4553
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 4553 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 4553
From Windows
Test-NetConnection HOST -Port 4553

Block port 4553 in the firewall

ufw
sudo ufw deny 4553/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 4553 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 4553 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 4553' -Direction Inbound -Protocol TCP -LocalPort 4553 -Action Block

Related ports

All port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.