CyberHunter
LinkedIn profile - Bastien Cordier Email: contact@bastiencordier.pro
// Other services

Port 436: DNA-CML

Port 436 is assigned by IANA to dna-cml (DNA-CML).

436

How dna-cml works

Other services
client:436dna-cmlresponse client:436dna-cmlresponse

The client sends a request to port 436 and the dna-cml 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
Well-known (0-1023)
Category
Other services
01 Security

Is port 436 dangerous?

We have no specific security note for port 436. 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 436

ServicePortTransportDescriptionReferenceUpdated
dna-cml 436 TCP, UDP DNA-CML - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 436, and is it reachable?

Linux

sudo ss -ltnup 'sport = :436'      # process listening on 436
sudo lsof -nP -i :436

macOS

sudo lsof -nP -i :436

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 436 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 436
netstat -ano | findstr :436

From another machine

nmap -p 436 -sV <host>
sudo nmap -sU -p 436 <host>
nc -zv <host> 436

Block it in the firewall

sudo ufw deny 436/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 436" -Direction Inbound -LocalPort 436 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 436 used for?

Port 436 is assigned by IANA to dna-cml (DNA-CML).

Is port 436 TCP or UDP?

Port 436 is registered for TCP and UDP.

Is it safe to open port 436?

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 436 is open?

On Linux run "ss -ltnup 'sport = :436'", on macOS "lsof -nP -i :436", and on Windows "netstat -ano | findstr :436" to see the local process. From another machine, "nmap -p 436 <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