CyberHunter
Local dataset, no network
// Other services

Port 263: HDAP

Port 263 is assigned by IANA to hdap (HDAP).

263

How hdap works

Other services
client:263hdapresponse client:263hdapresponse

The client sends a request to port 263 and the hdap 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 263 dangerous?

We have no specific security note for port 263. 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 263

ServicePortTransportDescriptionReferenceUpdated
hdap 263 TCP, UDP HDAP - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 263, and is it reachable?

Linux

sudo ss -ltnup 'sport = :263'      # process listening on 263
sudo lsof -nP -i :263

macOS

sudo lsof -nP -i :263

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 263 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 263
netstat -ano | findstr :263

From another machine

nmap -p 263 -sV <host>
sudo nmap -sU -p 263 <host>
nc -zv <host> 263

Block it in the firewall

sudo ufw deny 263/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 263" -Direction Inbound -LocalPort 263 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 263 used for?

Port 263 is assigned by IANA to hdap (HDAP).

Is port 263 TCP or UDP?

Port 263 is registered for TCP and UDP.

Is it safe to open port 263?

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 263 is open?

On Linux run "ss -ltnup 'sport = :263'", on macOS "lsof -nP -i :263", and on Windows "netstat -ano | findstr :263" to see the local process. From another machine, "nmap -p 263 <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