- 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 767: phone
Port 767 is assigned by IANA to phonebook (phone).
767
How phonebook works
Voice & chatPort 767 sets up the call (who calls whom), then the voice travels as a stream of audio packets.
- Transport
- TCP · UDP
- Exposure risk
- not rated depends on the program listening
- Encryption
- Unknownnot stated by the registry
- IANA status
- Assigned1 registered service
- Range
- Well-known (0-1023)
- Category
- Voice & chat
Is port 767 dangerous?
We have no specific security note for port 767. Its risk depends on the program actually listening on it. General advice for voice & chat services:
IANA registry entries for port 767
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| phonebook | 767 | TCP, UDP | phone | - | - |
// source: IANA service name and port number registry
Which program uses port 767, and is it reachable?
Linux
sudo ss -ltnup 'sport = :767' # process listening on 767
sudo lsof -nP -i :767macOS
sudo lsof -nP -i :767
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 767 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 767 netstat -ano | findstr :767
From another machine
nmap -p 767 -sV <host> sudo nmap -sU -p 767 <host> nc -zv <host> 767
Block it in the firewall
sudo ufw deny 767/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 767" -Direction Inbound -LocalPort 767 -Protocol TCP -Action Block # Windows
What is port 767 used for?
Port 767 is assigned by IANA to phonebook (phone).
Is port 767 TCP or UDP?
Port 767 is registered for TCP and UDP.
Is it safe to open port 767?
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 767 is open?
On Linux run "ss -ltnup 'sport = :767'", on macOS "lsof -nP -i :767", and on Windows "netstat -ano | findstr :767" to see the local process. From another machine, "nmap -p 767 <host>" shows whether it is reachable.