- Close the port if nothing on the host needs it.
- Identify the process that listens on it (commands below) before opening it in a firewall.
- Expose a service only to the networks that use it.
Port 6688: CleverView for TCP/IP Message Service
Port 6688 is assigned by IANA to clever-tcpip (CleverView for TCP/IP Message Service).
How clever-tcpip works
Other servicesThe client sends a request to port 6688 and the clever-tcpip service answers.
- 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
- Other services
Is port 6688 dangerous?
We have no specific security note for port 6688. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 6688
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| clever-tcpip | 6688 | TCP | CleverView for TCP/IP Message Service | - | 2009-10-13 |
| - | 6688 | - | Reserved | - | - |
// source: IANA service name and port number registry
Which program uses port 6688, and is it reachable?
Linux
sudo ss -ltnup 'sport = :6688' # process listening on 6688
sudo lsof -nP -i :6688macOS
sudo lsof -nP -i :6688
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 6688 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 6688 netstat -ano | findstr :6688
From another machine
nmap -p 6688 -sV <host> nc -zv <host> 6688
Block it in the firewall
sudo ufw deny 6688/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 6688" -Direction Inbound -LocalPort 6688 -Protocol TCP -Action Block # Windows
What is port 6688 used for?
Port 6688 is assigned by IANA to clever-tcpip (CleverView for TCP/IP Message Service).
Is port 6688 TCP or UDP?
Port 6688 is registered for TCP.
Is it safe to open port 6688?
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. Close the port if nothing on the host needs it.
How do I check if port 6688 is open?
On Linux run "ss -ltnup 'sport = :6688'", on macOS "lsof -nP -i :6688", and on Windows "netstat -ano | findstr :6688" to see the local process. From another machine, "nmap -p 6688 <host>" shows whether it is reachable.