- 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 507: crs
Port 507 is assigned by IANA to crs (crs).
507
How crs works
Other servicesThe client sends a request to port 507 and the crs 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
- Well-known (0-1023)
- Category
- Other services
Is port 507 dangerous?
We have no specific security note for port 507. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 507
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| crs | 507 | TCP, UDP | crs | - | - |
// source: IANA service name and port number registry
Which program uses port 507, and is it reachable?
Linux
sudo ss -ltnup 'sport = :507' # process listening on 507
sudo lsof -nP -i :507macOS
sudo lsof -nP -i :507
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 507 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 507 netstat -ano | findstr :507
From another machine
nmap -p 507 -sV <host> sudo nmap -sU -p 507 <host> nc -zv <host> 507
Block it in the firewall
sudo ufw deny 507/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 507" -Direction Inbound -LocalPort 507 -Protocol TCP -Action Block # Windows
What is port 507 used for?
Port 507 is assigned by IANA to crs (crs).
Is port 507 TCP or UDP?
Port 507 is registered for TCP and UDP.
Is it safe to open port 507?
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 507 is open?
On Linux run "ss -ltnup 'sport = :507'", on macOS "lsof -nP -i :507", and on Windows "netstat -ano | findstr :507" to see the local process. From another machine, "nmap -p 507 <host>" shows whether it is reachable.
Other other services ports
:4444 Metasploit default / krb524 tcp · udp · high risk :31337 Back Orifice / elite tcp · udp · high risk :1 TCP Port Service Multiplexer tcp · udp :5 Remote Job Entry tcp · udp :9 Discard tcp · udp · sctp · dccp :11 Active Users tcp · udp :17 Quote of the Day tcp · udp :18 Message Send Protocol (historic) tcp · udp