CyberHunter
// Network services

Port 9021: Pangolin Identification

Port 9021 is assigned by IANA to panagolin-ident (Pangolin Identification).

9021

How panagolin-ident works

Network services
client:9021panagolin-identresponse client:9021panagolin-identresponse

The client sends a request to port 9021 and the panagolin-ident 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)
01 Security

Is port 9021 dangerous?

We have no specific security note for port 9021. Its risk depends on the program actually listening on it. General advice for network services services:

  • Answer only the networks that need the service (no open resolvers, relays or reflectors).
  • UDP services can be abused for DDoS amplification: rate-limit or block them at the edge.
  • Disable legacy test services that have no use in production.
02 Registry

IANA registry entries for port 9021

ServicePortTransportDescriptionReferenceUpdated
panagolin-ident 9021 TCP, UDP Pangolin Identification - 2002-03

// source: IANA service name and port number registry

03 Check it

Which program uses port 9021, and is it reachable?

Linux

sudo ss -ltnup 'sport = :9021'      # process listening on 9021
sudo lsof -nP -i :9021

macOS

sudo lsof -nP -i :9021

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 9021 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 9021
netstat -ano | findstr :9021

From another machine

nmap -p 9021 -sV <host>
sudo nmap -sU -p 9021 <host>
nc -zv <host> 9021

Block it in the firewall

sudo ufw deny 9021/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 9021" -Direction Inbound -LocalPort 9021 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 9021 used for?

Port 9021 is assigned by IANA to panagolin-ident (Pangolin Identification).

Is port 9021 TCP or UDP?

Port 9021 is registered for TCP and UDP.

Is it safe to open port 9021?

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. Answer only the networks that need the service (no open resolvers, relays or reflectors).

How do I check if port 9021 is open?

On Linux run "ss -ltnup 'sport = :9021'", on macOS "lsof -nP -i :9021", and on Windows "netstat -ano | findstr :9021" to see the local process. From another machine, "nmap -p 9021 <host>" shows whether it is reachable.

05 Related