CyberHunter
// File transfer & sharing

Port 487: saft Simple Asynchronous File Transfer

Port 487 is assigned by IANA to saft (saft Simple Asynchronous File Transfer).

487

How saft works

File transfer & sharing
client:4871/32/33/3saft client:4871/32/33/3saft

Files are sent over port 487 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 487 dangerous?

We have no specific security note for port 487. 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 487

ServicePortTransportDescriptionReferenceUpdated
saft 487 TCP, UDP saft Simple Asynchronous File Transfer - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 487, and is it reachable?

Linux

sudo ss -ltnup 'sport = :487'      # process listening on 487
sudo lsof -nP -i :487

macOS

sudo lsof -nP -i :487

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 487 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 487
netstat -ano | findstr :487

From another machine

nmap -p 487 -sV <host>
sudo nmap -sU -p 487 <host>
nc -zv <host> 487

Block it in the firewall

sudo ufw deny 487/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 487" -Direction Inbound -LocalPort 487 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 487 used for?

Port 487 is assigned by IANA to saft (saft Simple Asynchronous File Transfer).

Is port 487 TCP or UDP?

Port 487 is registered for TCP and UDP.

Is it safe to open port 487?

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 487 is open?

On Linux run "ss -ltnup 'sport = :487'", on macOS "lsof -nP -i :487", and on Windows "netstat -ano | findstr :487" to see the local process. From another machine, "nmap -p 487 <host>" shows whether it is reachable.

05 Related