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

Port 41111: Foursticks QoS Protocol

Port 41111 is assigned by IANA to fs-qos (Foursticks QoS Protocol).

41111

How fs-qos works

Other services
client:41111fs-qosresponse client:41111fs-qosresponse

The client sends a request to port 41111 and the fs-qos 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)
Category
Other services
01 Security

Is port 41111 dangerous?

We have no specific security note for port 41111. 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 41111

ServicePortTransportDescriptionReferenceUpdated
fs-qos 41111 TCP, UDP Foursticks QoS Protocol - 2002-04

// source: IANA service name and port number registry

03 Check it

Which program uses port 41111, and is it reachable?

Linux

sudo ss -ltnup 'sport = :41111'      # process listening on 41111
sudo lsof -nP -i :41111

macOS

sudo lsof -nP -i :41111

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 41111 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 41111
netstat -ano | findstr :41111

From another machine

nmap -p 41111 -sV <host>
sudo nmap -sU -p 41111 <host>
nc -zv <host> 41111

Block it in the firewall

sudo ufw deny 41111/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 41111" -Direction Inbound -LocalPort 41111 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 41111 used for?

Port 41111 is assigned by IANA to fs-qos (Foursticks QoS Protocol).

Is port 41111 TCP or UDP?

Port 41111 is registered for TCP and UDP.

Is it safe to open port 41111?

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 41111 is open?

On Linux run "ss -ltnup 'sport = :41111'", on macOS "lsof -nP -i :41111", and on Windows "netstat -ano | findstr :41111" to see the local process. From another machine, "nmap -p 41111 <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