HTTPfy

Port 4423 (thingkit)

IANA assigns port 4423 to thingkit: thingkit secure mesh.

Registered (user) port, 1024-49151 TCP

IANA assignment

Service nameProtoDescriptionAssigneeReference
thingkit TCP thingkit secure mesh thingkit inc. -

Registry dates for this port: registered 2016-06-27.

Check what is listening on port 4423

Linux: is anything listening on TCP 4423?
sudo ss -tlnp 'sport = :4423'
Linux / macOS: which process owns the port
sudo lsof -nP -i :4423
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':4423 '
Windows (Command Prompt)
netstat -ano | findstr :4423
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 4423 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 4423
From Windows
Test-NetConnection HOST -Port 4423

Block port 4423 in the firewall

ufw
sudo ufw deny 4423/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 4423 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 4423 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 4423' -Direction Inbound -Protocol TCP -LocalPort 4423 -Action Block

Related ports

4421scaleft4422tsepisp4425netrockey64426beacon-port-2

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