- Use strong credentials and TLS for signalling.
- Rate-limit registrations to stop extension scanning and toll fraud.
- Alert on unexpected chat protocols leaving servers (possible command and control).
Port 5349: STUN Behavior Discovery over TLS
Port 5349 is assigned by IANA to stun-behaviors (STUN Behavior Discovery over TLS), stuns (Session Traversal Utilities for NAT (STUN) port), turns (TURN over TLS).
5349
How stun-behaviors works
Voice & chatPort 5349 sets up the call (who calls whom), then the voice travels as a stream of audio packets. Everything is encrypted: someone on the path only sees unreadable bytes.
- Transport
- TCP · UDP
- Exposure risk
- not rated depends on the program listening
- Encryption
- EncryptedTLS or built-in crypto
- IANA status
- Assigned3 registered services
- Range
- Registered (1024-49151)
- Category
- Voice & chat
Is port 5349 dangerous?
We have no specific security note for port 5349. Its risk depends on the program actually listening on it. General advice for voice & chat services:
IANA registry entries for port 5349
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| stun-behaviors | 5349 | TCP, UDP | STUN Behavior Discovery over TLS | RFC 5780 | - |
| stuns | 5349 | TCP, UDP | Session Traversal Utilities for NAT (STUN) port | RFC 8489 | 2019-03-28 |
| turns | 5349 | TCP, UDP | TURN over TLS | RFC 8656 | 2019-08-02 |
// source: IANA service name and port number registry
Which program uses port 5349, and is it reachable?
Linux
sudo ss -ltnup 'sport = :5349' # process listening on 5349
sudo lsof -nP -i :5349macOS
sudo lsof -nP -i :5349
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 5349 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 5349 netstat -ano | findstr :5349
From another machine
nmap -p 5349 -sV <host> sudo nmap -sU -p 5349 <host> nc -zv <host> 5349
Block it in the firewall
sudo ufw deny 5349/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 5349" -Direction Inbound -LocalPort 5349 -Protocol TCP -Action Block # Windows
What is port 5349 used for?
Port 5349 is assigned by IANA to stun-behaviors (STUN Behavior Discovery over TLS), stuns (Session Traversal Utilities for NAT (STUN) port), turns (TURN over TLS).
Is port 5349 TCP or UDP?
Port 5349 is registered for TCP and UDP.
Is it safe to open port 5349?
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. Use strong credentials and TLS for signalling.
How do I check if port 5349 is open?
On Linux run "ss -ltnup 'sport = :5349'", on macOS "lsof -nP -i :5349", and on Windows "netstat -ano | findstr :5349" to see the local process. From another machine, "nmap -p 5349 <host>" shows whether it is reachable.