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Port 6690 (cleverdetect)

IANA assigns port 6690 to cleverdetect: CLEVERDetect Message Service.

Registered (user) port, 1024-49151 TCP

IANA assignment

Service nameProtoDescriptionAssigneeReference
cleverdetect TCP CLEVERDetect Message Service Applied Expert Systems Inc -

Registry dates for this port: registered 2014-12-03.

Check what is listening on port 6690

Linux: is anything listening on TCP 6690?
sudo ss -tlnp 'sport = :6690'
Linux / macOS: which process owns the port
sudo lsof -nP -i :6690
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':6690 '
Windows (Command Prompt)
netstat -ano | findstr :6690
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 6690 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 6690
From Windows
Test-NetConnection HOST -Port 6690

Block port 6690 in the firewall

ufw
sudo ufw deny 6690/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 6690 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 6690 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 6690' -Direction Inbound -Protocol TCP -LocalPort 6690 -Action Block

Related ports

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