- Keep directory and authentication services on internal networks.
- Require signing or TLS and disable anonymous queries.
- Monitor authentication failures for spraying and brute force.
Port 9389: Active Directory Web Services
Port 9389 is assigned by IANA to adws (Active Directory Web Services).
9389
How adws works
Directory & authenticationThe client proves who it is on port 9389 and gets an answer (or a ticket) it can use with other services.
- 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
- Directory & authentication
Is port 9389 dangerous?
We have no specific security note for port 9389. Its risk depends on the program actually listening on it. General advice for directory & authentication services:
IANA registry entries for port 9389
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| adws | 9389 | TCP | Active Directory Web Services | - | 2008-12-24 |
| - | 9389 | - | Reserved | - | - |
// source: IANA service name and port number registry
Which program uses port 9389, and is it reachable?
Linux
sudo ss -ltnup 'sport = :9389' # process listening on 9389
sudo lsof -nP -i :9389macOS
sudo lsof -nP -i :9389
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 9389 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 9389 netstat -ano | findstr :9389
From another machine
nmap -p 9389 -sV <host> nc -zv <host> 9389
Block it in the firewall
sudo ufw deny 9389/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 9389" -Direction Inbound -LocalPort 9389 -Protocol TCP -Action Block # Windows
What is port 9389 used for?
Port 9389 is assigned by IANA to adws (Active Directory Web Services).
Is port 9389 TCP or UDP?
Port 9389 is registered for TCP.
Is it safe to open port 9389?
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. Keep directory and authentication services on internal networks.
How do I check if port 9389 is open?
On Linux run "ss -ltnup 'sport = :9389'", on macOS "lsof -nP -i :9389", and on Windows "netstat -ano | findstr :9389" to see the local process. From another machine, "nmap -p 9389 <host>" shows whether it is reachable.
Other directory & authentication ports
:389 LDAP tcp · udp · high risk :636 LDAPS tcp · udp · moderate risk :88 Kerberos tcp · udp · high risk :3268 Global Catalog (LDAP) tcp · udp · high risk :1812 RADIUS udp · tcp · moderate risk :31 MSG Authentication tcp · udp :49 Login Host Protocol (TACACS) tcp · udp :56 XNS Authentication tcp · udp