All ports

Port3901/TCP

nimsh

Port

3901

Protocol

TCP

Category

Registered

Service

nimsh

What is port 3901?

Port 3901/TCP is a Registered port, registered with IANA for specific applications. It is associated with the nimsh service.

NIM Service Handler

Useful commands

nmapnmap -p 3901 -sV example.com
netcatnc -zv example.com 3901
curlcurl -v http://example.com:3901/
telnettelnet example.com 3901
bash(echo > /dev/tcp/example.com/3901) 2>/dev/null

Firewall commands

UFWAllow
sudo ufw allow 3901/tcp
Deny
sudo ufw deny 3901/tcp
iptablesAllow
sudo iptables -A INPUT -p tcp --dport 3901 -j ACCEPT
Deny
sudo iptables -D INPUT -p tcp --dport 3901 -j ACCEPT
firewalldAllow
sudo firewall-cmd --permanent --add-port=3901/tcp
WindowsAllow
netsh advfirewall firewall add rule name="Open Port 3901" dir=in action=allow protocol=TCP localport=3901

Security Risks

  • Unauthorized access to the service
  • Data exposure if the service is unauthenticated
  • Outdated versions with vulnerabilities
  • Incorrect service configuration

Frequently Asked Questions

What service runs on port 3901/TCP?

Port 3901/TCP is associated with the nimsh service. NIM Service Handler

Is it safe to expose port 3901 to the Internet?

It depends on the service and configuration. Port 3901 (nimsh) is a Registered port. If you need to expose it, keep the service updated, use strong authentication, and configure a firewall. It's always recommended to restrict access by IP when possible.

How do I check if port 3901 is open?

You can use nmap: `nmap -p 3901 -sV example.com`, netcat: `nc -zv example.com 3901`, or the bash command: `(echo > /dev/tcp/example.com/3901) 2>/dev/null && echo "Open" || echo "Closed"`.

How do I open or close port 3901 on my firewall?

On Linux with UFW: `sudo ufw allow 3901/tcp` (open) or `sudo ufw deny 3901/tcp` (close). With iptables: `sudo iptables -A INPUT -p tcp --dport 3901 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 3901" dir=in action=allow protocol=TCP localport=3901`.

What applications and services use port 3901?

Port 3901/TCP is used by the nimsh service. Specific uses depend on the software and configuration. Check our related tools section for more information.

Related ports