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

Port 1026: Calendar Access Protocol

Port 1026 is assigned by IANA to cap (Calendar Access Protocol).

1026

How cap works

Other services
client:1026capresponse client:1026capresponse

The client sends a request to port 1026 and the cap 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 1026 dangerous?

We have no specific security note for port 1026. 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 1026

ServicePortTransportDescriptionReferenceUpdated
cap 1026 TCP, UDP Calendar Access Protocol - 2010-12-09

// source: IANA service name and port number registry

03 Check it

Which program uses port 1026, and is it reachable?

Linux

sudo ss -ltnup 'sport = :1026'      # process listening on 1026
sudo lsof -nP -i :1026

macOS

sudo lsof -nP -i :1026

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 1026 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 1026
netstat -ano | findstr :1026

From another machine

nmap -p 1026 -sV <host>
sudo nmap -sU -p 1026 <host>
nc -zv <host> 1026

Block it in the firewall

sudo ufw deny 1026/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 1026" -Direction Inbound -LocalPort 1026 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 1026 used for?

Port 1026 is assigned by IANA to cap (Calendar Access Protocol).

Is port 1026 TCP or UDP?

Port 1026 is registered for TCP and UDP.

Is it safe to open port 1026?

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 1026 is open?

On Linux run "ss -ltnup 'sport = :1026'", on macOS "lsof -nP -i :1026", and on Windows "netstat -ano | findstr :1026" to see the local process. From another machine, "nmap -p 1026 <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