CyberHunter
// File transfer & sharing

Port 564: plan 9 file service

Port 564 is assigned by IANA to 9pfs (plan 9 file service).

564

How 9pfs works

File transfer & sharing
client:5641/32/33/39pfs client:5641/32/33/39pfs

Files are sent over port 564 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
Well-known (0-1023)
01 Security

Is port 564 dangerous?

We have no specific security note for port 564. Its risk depends on the program actually listening on it. General advice for file transfer & sharing services:

  • 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.
02 Registry

IANA registry entries for port 564

ServicePortTransportDescriptionReferenceUpdated
9pfs 564 TCP, UDP plan 9 file service - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 564, and is it reachable?

Linux

sudo ss -ltnup 'sport = :564'      # process listening on 564
sudo lsof -nP -i :564

macOS

sudo lsof -nP -i :564

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 564 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 564
netstat -ano | findstr :564

From another machine

nmap -p 564 -sV <host>
sudo nmap -sU -p 564 <host>
nc -zv <host> 564

Block it in the firewall

sudo ufw deny 564/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 564" -Direction Inbound -LocalPort 564 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 564 used for?

Port 564 is assigned by IANA to 9pfs (plan 9 file service).

Is port 564 TCP or UDP?

Port 564 is registered for TCP and UDP.

Is it safe to open port 564?

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 564 is open?

On Linux run "ss -ltnup 'sport = :564'", on macOS "lsof -nP -i :564", and on Windows "netstat -ano | findstr :564" to see the local process. From another machine, "nmap -p 564 <host>" shows whether it is reachable.

05 Related