CyberHunter
// Other services

Port 1857: DataCaptor

Port 1857 is assigned by IANA to datacaptor (DataCaptor).

1857

How datacaptor works

Other services
client:1857datacaptorresponse client:1857datacaptorresponse

The client sends a request to port 1857 and the datacaptor service answers.

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)
01 Security

Is port 1857 dangerous?

We have no specific security note for port 1857. Its risk depends on the program actually listening on it. General advice for other services services:

  • Close the port if nothing on the host needs it.
  • Identify the process that listens on it (commands below) before opening it in a firewall.
  • Expose a service only to the networks that use it.
02 Registry

IANA registry entries for port 1857

ServicePortTransportDescriptionReferenceUpdated
datacaptor 1857 TCP, UDP DataCaptor - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 1857, and is it reachable?

Linux

sudo ss -ltnup 'sport = :1857'      # process listening on 1857
sudo lsof -nP -i :1857

macOS

sudo lsof -nP -i :1857

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 1857 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 1857
netstat -ano | findstr :1857

From another machine

nmap -p 1857 -sV <host>
sudo nmap -sU -p 1857 <host>
nc -zv <host> 1857

Block it in the firewall

sudo ufw deny 1857/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 1857" -Direction Inbound -LocalPort 1857 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 1857 used for?

Port 1857 is assigned by IANA to datacaptor (DataCaptor).

Is port 1857 TCP or UDP?

Port 1857 is registered for TCP and UDP.

Is it safe to open port 1857?

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. Close the port if nothing on the host needs it.

How do I check if port 1857 is open?

On Linux run "ss -ltnup 'sport = :1857'", on macOS "lsof -nP -i :1857", and on Windows "netstat -ano | findstr :1857" to see the local process. From another machine, "nmap -p 1857 <host>" shows whether it is reachable.

05 Related