CyberHunter
Local dataset, no network
// Other services

Port 6209: QMTP over TLS

Port 6209 is assigned by IANA to qmtps (QMTP over TLS).

6209

How qmtps works

Other services
client:6209#%&@!x9response? client:6209#%&@!x9response?

The client sends a request to port 6209 and the qmtps service answers. Everything is encrypted: someone on the path only sees unreadable bytes.

Transport
TCP · UDP
Exposure risk
not rated depends on the program listening
Encryption
EncryptedTLS or built-in crypto
IANA status
Assigned1 registered service
Range
Registered (1024-49151)
Category
Other services
01 Security

Is port 6209 dangerous?

We have no specific security note for port 6209. 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 6209

ServicePortTransportDescriptionReferenceUpdated
qmtps 6209 TCP, UDP QMTP over TLS - 2015-01-09

// source: IANA service name and port number registry

03 Check it

Which program uses port 6209, and is it reachable?

Linux

sudo ss -ltnup 'sport = :6209'      # process listening on 6209
sudo lsof -nP -i :6209

macOS

sudo lsof -nP -i :6209

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 6209 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 6209
netstat -ano | findstr :6209

From another machine

nmap -p 6209 -sV <host>
sudo nmap -sU -p 6209 <host>
nc -zv <host> 6209

Block it in the firewall

sudo ufw deny 6209/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 6209" -Direction Inbound -LocalPort 6209 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 6209 used for?

Port 6209 is assigned by IANA to qmtps (QMTP over TLS).

Is port 6209 TCP or UDP?

Port 6209 is registered for TCP and UDP.

Is it safe to open port 6209?

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 6209 is open?

On Linux run "ss -ltnup 'sport = :6209'", on macOS "lsof -nP -i :6209", and on Windows "netstat -ano | findstr :6209" to see the local process. From another machine, "nmap -p 6209 <host>" shows whether it is reachable.

05 Related
:4444 Metasploit default / krb524 tcp · udp · high risk :31337 Back Orifice / elite tcp · udp · high risk :1 TCP Port Service Multiplexer tcp · udp :5 Remote Job Entry tcp · udp :9 Discard tcp · udp · sctp · dccp :11 Active Users tcp · udp :17 Quote of the Day tcp · udp :18 Message Send Protocol (historic) tcp · udp

Latest vulnerability news

All news