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

Port 437: comscm

Port 437 is assigned by IANA to comscm (comscm).

437

How comscm works

Other services
client:437comscmresponse client:437comscmresponse

The client sends a request to port 437 and the comscm 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 437 dangerous?

We have no specific security note for port 437. 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 437

ServicePortTransportDescriptionReferenceUpdated
comscm 437 TCP, UDP comscm - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 437, and is it reachable?

Linux

sudo ss -ltnup 'sport = :437'      # process listening on 437
sudo lsof -nP -i :437

macOS

sudo lsof -nP -i :437

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 437 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 437
netstat -ano | findstr :437

From another machine

nmap -p 437 -sV <host>
sudo nmap -sU -p 437 <host>
nc -zv <host> 437

Block it in the firewall

sudo ufw deny 437/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 437" -Direction Inbound -LocalPort 437 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 437 used for?

Port 437 is assigned by IANA to comscm (comscm).

Is port 437 TCP or UDP?

Port 437 is registered for TCP and UDP.

Is it safe to open port 437?

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 437 is open?

On Linux run "ss -ltnup 'sport = :437'", on macOS "lsof -nP -i :437", and on Windows "netstat -ano | findstr :437" to see the local process. From another machine, "nmap -p 437 <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