HTTPfy

Port 18242 (iclid)

IANA assigns port 18242 to iclid: Checkpoint router monitoring.

Registered (user) port, 1024-49151 TCP

IANA assignment

Service nameProtoDescriptionAssigneeReference
iclid TCP Checkpoint router monitoring Check Point Software -

Registry dates for this port: registered 2012-06-28.

Check what is listening on port 18242

Linux: is anything listening on TCP 18242?
sudo ss -tlnp 'sport = :18242'
Linux / macOS: which process owns the port
sudo lsof -nP -i :18242
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':18242 '
Windows (Command Prompt)
netstat -ano | findstr :18242
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 18242 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 18242
From Windows
Test-NetConnection HOST -Port 18242

Block port 18242 in the firewall

ufw
sudo ufw deny 18242/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 18242 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 18242 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 18242' -Direction Inbound -Protocol TCP -LocalPort 18242 -Action Block

Related ports

18187opsec-ela18241checkpoint-rtm18243clusterxl18262gv-pf

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