- 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.
Port 3646: XSS Server Port
Port 3646 is assigned by IANA to xss-srv-port (XSS Server Port).
How xss-srv-port works
Other servicesThe client sends a request to port 3646 and the xss-srv-port 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
Is port 3646 dangerous?
We have no specific security note for port 3646. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 3646
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| xss-srv-port | 3646 | TCP, UDP | XSS Server Port | - | 2003-01 |
// source: IANA service name and port number registry
Which program uses port 3646, and is it reachable?
Linux
sudo ss -ltnup 'sport = :3646' # process listening on 3646
sudo lsof -nP -i :3646macOS
sudo lsof -nP -i :3646
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3646 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 3646 netstat -ano | findstr :3646
From another machine
nmap -p 3646 -sV <host> sudo nmap -sU -p 3646 <host> nc -zv <host> 3646
Block it in the firewall
sudo ufw deny 3646/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 3646" -Direction Inbound -LocalPort 3646 -Protocol TCP -Action Block # Windows
What is port 3646 used for?
Port 3646 is assigned by IANA to xss-srv-port (XSS Server Port).
Is port 3646 TCP or UDP?
Port 3646 is registered for TCP and UDP.
Is it safe to open port 3646?
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 3646 is open?
On Linux run "ss -ltnup 'sport = :3646'", on macOS "lsof -nP -i :3646", and on Windows "netstat -ano | findstr :3646" to see the local process. From another machine, "nmap -p 3646 <host>" shows whether it is reachable.