- Require authentication on cameras and media servers.
- Keep IP cameras and recorders off the Internet; use a VPN for remote viewing.
- Update device firmware.
Port 537: Networked Media Streaming Protocol
Port 537 is assigned by IANA to nmsp (Networked Media Streaming Protocol).
537
How nmsp works
Media & streamingThe device streams video frames over port 537, continuously, as they are captured.
- 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
- Media & streaming
Is port 537 dangerous?
We have no specific security note for port 537. Its risk depends on the program actually listening on it. General advice for media & streaming services:
IANA registry entries for port 537
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| nmsp | 537 | TCP, UDP | Networked Media Streaming Protocol | - | - |
// source: IANA service name and port number registry
Which program uses port 537, and is it reachable?
Linux
sudo ss -ltnup 'sport = :537' # process listening on 537
sudo lsof -nP -i :537macOS
sudo lsof -nP -i :537
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 537 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 537 netstat -ano | findstr :537
From another machine
nmap -p 537 -sV <host> sudo nmap -sU -p 537 <host> nc -zv <host> 537
Block it in the firewall
sudo ufw deny 537/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 537" -Direction Inbound -LocalPort 537 -Protocol TCP -Action Block # Windows
What is port 537 used for?
Port 537 is assigned by IANA to nmsp (Networked Media Streaming Protocol).
Is port 537 TCP or UDP?
Port 537 is registered for TCP and UDP.
Is it safe to open port 537?
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. Require authentication on cameras and media servers.
How do I check if port 537 is open?
On Linux run "ss -ltnup 'sport = :537'", on macOS "lsof -nP -i :537", and on Windows "netstat -ano | findstr :537" to see the local process. From another machine, "nmap -p 537 <host>" shows whether it is reachable.