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

Port 2153: Control Protocol

Port 2153 is assigned by IANA to ctlptc (Control Protocol).

2153

How ctlptc works

Other services
client:2153ctlptcresponse client:2153ctlptcresponse

The client sends a request to port 2153 and the ctlptc 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 2153 dangerous?

We have no specific security note for port 2153. 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 2153

ServicePortTransportDescriptionReferenceUpdated
ctlptc 2153 TCP, UDP Control Protocol - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 2153, and is it reachable?

Linux

sudo ss -ltnup 'sport = :2153'      # process listening on 2153
sudo lsof -nP -i :2153

macOS

sudo lsof -nP -i :2153

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 2153 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 2153
netstat -ano | findstr :2153

From another machine

nmap -p 2153 -sV <host>
sudo nmap -sU -p 2153 <host>
nc -zv <host> 2153

Block it in the firewall

sudo ufw deny 2153/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 2153" -Direction Inbound -LocalPort 2153 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 2153 used for?

Port 2153 is assigned by IANA to ctlptc (Control Protocol).

Is port 2153 TCP or UDP?

Port 2153 is registered for TCP and UDP.

Is it safe to open port 2153?

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 2153 is open?

On Linux run "ss -ltnup 'sport = :2153'", on macOS "lsof -nP -i :2153", and on Windows "netstat -ano | findstr :2153" to see the local process. From another machine, "nmap -p 2153 <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