All ports

Port8991/TCP

https-wmap

Port

8991

Protocol

TCP

Category

Registered

Service

https-wmap

What is port 8991?

Port 8991/TCP is a Registered port, registered with IANA for specific applications. It is associated with the https-wmap service.

webmail HTTPS service

Useful commands

nmapnmap -p 8991 -sV example.com
netcatnc -zv example.com 8991
curlcurl -v http://example.com:8991/
telnettelnet example.com 8991
bash(echo > /dev/tcp/example.com/8991) 2>/dev/null

Firewall commands

UFWAllow
sudo ufw allow 8991/tcp
Deny
sudo ufw deny 8991/tcp
iptablesAllow
sudo iptables -A INPUT -p tcp --dport 8991 -j ACCEPT
Deny
sudo iptables -D INPUT -p tcp --dport 8991 -j ACCEPT
firewalldAllow
sudo firewall-cmd --permanent --add-port=8991/tcp
WindowsAllow
netsh advfirewall firewall add rule name="Open Port 8991" dir=in action=allow protocol=TCP localport=8991

Security Risks

  • Incorrect TLS/SSL configuration
  • Man-in-the-Middle attacks if certificate is invalid
  • Protocol implementation vulnerabilities
  • Exposure of web services with weak authentication

Frequently Asked Questions

What service runs on port 8991/TCP?

Port 8991/TCP is associated with the https-wmap service. webmail HTTPS service

Is it safe to expose port 8991 to the Internet?

It depends on the service and configuration. Port 8991 (https-wmap) 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 8991 is open?

You can use nmap: `nmap -p 8991 -sV example.com`, netcat: `nc -zv example.com 8991`, or the bash command: `(echo > /dev/tcp/example.com/8991) 2>/dev/null && echo "Open" || echo "Closed"`.

How do I open or close port 8991 on my firewall?

On Linux with UFW: `sudo ufw allow 8991/tcp` (open) or `sudo ufw deny 8991/tcp` (close). With iptables: `sudo iptables -A INPUT -p tcp --dport 8991 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 8991" dir=in action=allow protocol=TCP localport=8991`.

What applications and services use port 8991?

Port 8991/TCP is used by the https-wmap service. Specific uses depend on the software and configuration. Check our related tools section for more information.

Related ports