- Prefer encrypted protocols (SFTP, FTPS, SMB 3 with encryption).
- Disable anonymous access and restrict shares or exports to known hosts.
- Never publish file sharing protocols to the Internet.
Port 3020: CIFS
Port 3020 is assigned by IANA to cifs (CIFS).
How cifs works
File transfer & sharingFiles are sent over port 3020 in pieces and reassembled on the other side.
- 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
- File transfer & sharing
Is port 3020 dangerous?
We have no specific security note for port 3020. Its risk depends on the program actually listening on it. General advice for file transfer & sharing services:
IANA registry entries for port 3020
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| cifs | 3020 | TCP, UDP | CIFS | - | - |
// source: IANA service name and port number registry
Which program uses port 3020, and is it reachable?
Linux
sudo ss -ltnup 'sport = :3020' # process listening on 3020
sudo lsof -nP -i :3020macOS
sudo lsof -nP -i :3020
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3020 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 3020 netstat -ano | findstr :3020
From another machine
nmap -p 3020 -sV <host> sudo nmap -sU -p 3020 <host> nc -zv <host> 3020
Block it in the firewall
sudo ufw deny 3020/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 3020" -Direction Inbound -LocalPort 3020 -Protocol TCP -Action Block # Windows
What is port 3020 used for?
Port 3020 is assigned by IANA to cifs (CIFS).
Is port 3020 TCP or UDP?
Port 3020 is registered for TCP and UDP.
Is it safe to open port 3020?
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. Prefer encrypted protocols (SFTP, FTPS, SMB 3 with encryption).
How do I check if port 3020 is open?
On Linux run "ss -ltnup 'sport = :3020'", on macOS "lsof -nP -i :3020", and on Windows "netstat -ano | findstr :3020" to see the local process. From another machine, "nmap -p 3020 <host>" shows whether it is reachable.