CyberHunter
// Network services

Port 3553: Red Box Recorder ADP

Port 3553 is assigned by IANA to rbr-discovery (Red Box Recorder ADP).

3553

How rbr-discovery works

Network services
client:3553rbr-discoveryresponse client:3553rbr-discoveryresponse

The client sends a request to port 3553 and the rbr-discovery 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 3553 dangerous?

We have no specific security note for port 3553. 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 3553

ServicePortTransportDescriptionReferenceUpdated
rbr-discovery 3553 TCP, UDP Red Box Recorder ADP - 2002-07

// source: IANA service name and port number registry

03 Check it

Which program uses port 3553, and is it reachable?

Linux

sudo ss -ltnup 'sport = :3553'      # process listening on 3553
sudo lsof -nP -i :3553

macOS

sudo lsof -nP -i :3553

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 3553 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 3553
netstat -ano | findstr :3553

From another machine

nmap -p 3553 -sV <host>
sudo nmap -sU -p 3553 <host>
nc -zv <host> 3553

Block it in the firewall

sudo ufw deny 3553/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 3553" -Direction Inbound -LocalPort 3553 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 3553 used for?

Port 3553 is assigned by IANA to rbr-discovery (Red Box Recorder ADP).

Is port 3553 TCP or UDP?

Port 3553 is registered for TCP and UDP.

Is it safe to open port 3553?

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 3553 is open?

On Linux run "ss -ltnup 'sport = :3553'", on macOS "lsof -nP -i :3553", and on Windows "netstat -ano | findstr :3553" to see the local process. From another machine, "nmap -p 3553 <host>" shows whether it is reachable.

05 Related