- Patch VPN gateways quickly: they are a top initial access target.
- Use certificates or MFA rather than shared secrets.
- Investigate unexpected tunnels and proxies: they are also attacker tools.
Port 9889: Port for Cable network related data proxy or repeater
Port 9889 is assigned by IANA to gt-proxy (Port for Cable network related data proxy or repeater).
9889
How gt-proxy works
VPN, tunnels & proxiesTraffic is wrapped in a tunnel between the two ends, so the network in between only sees the tunnel.
- Transport
- TCP · UDP
- 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
- VPN, tunnels & proxies
Is port 9889 dangerous?
We have no specific security note for port 9889. Its risk depends on the program actually listening on it. General advice for vpn, tunnels & proxies services:
IANA registry entries for port 9889
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| gt-proxy | 9889 | TCP, UDP | Port for Cable network related data proxy or repeater | - | 2010-07-07 |
// source: IANA service name and port number registry
Which program uses port 9889, and is it reachable?
Linux
sudo ss -ltnup 'sport = :9889' # process listening on 9889
sudo lsof -nP -i :9889macOS
sudo lsof -nP -i :9889
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 9889 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 9889 netstat -ano | findstr :9889
From another machine
nmap -p 9889 -sV <host> sudo nmap -sU -p 9889 <host> nc -zv <host> 9889
Block it in the firewall
sudo ufw deny 9889/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 9889" -Direction Inbound -LocalPort 9889 -Protocol TCP -Action Block # Windows
What is port 9889 used for?
Port 9889 is assigned by IANA to gt-proxy (Port for Cable network related data proxy or repeater).
Is port 9889 TCP or UDP?
Port 9889 is registered for TCP and UDP.
Is it safe to open port 9889?
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. Patch VPN gateways quickly: they are a top initial access target.
How do I check if port 9889 is open?
On Linux run "ss -ltnup 'sport = :9889'", on macOS "lsof -nP -i :9889", and on Windows "netstat -ano | findstr :9889" to see the local process. From another machine, "nmap -p 9889 <host>" shows whether it is reachable.