All ports
Port174/UDP
mailqPort
174
Protocol
UDP
Category
Well-Known
Service
mailq
What is port 174?
Port 174/UDP is a Well-Known port, assigned by IANA for widely recognized services. It is associated with the mailq service.
MAILQ
Useful commands
nmapnmap -p 174 -sV example.comnetcatnc -zv example.com 174curlcurl -v http://example.com:174/telnettelnet example.com 174bash(echo > /dev/udp/example.com/174) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 174/udpDeny
sudo ufw deny 174/udpiptablesAllow
sudo iptables -A INPUT -p udp --dport 174 -j ACCEPTDeny
sudo iptables -D INPUT -p udp --dport 174 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=174/udpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 174" dir=in action=allow protocol=UDP localport=174Security Risks
- Open relay used for spam
- Email spoofing
- Brute force attacks against email accounts
- Information disclosure in email headers
Frequently Asked Questions
What service runs on port 174/UDP?
Port 174/UDP is associated with the mailq service. MAILQ
Is it safe to expose port 174 to the Internet?
It depends on the service and configuration. Port 174 (mailq) is a Well-Known 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 174 is open?
You can use nmap: `nmap -p 174 -sV example.com`, netcat: `nc -zv example.com 174`, or the bash command: `(echo > /dev/udp/example.com/174) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 174 on my firewall?
On Linux with UFW: `sudo ufw allow 174/udp` (open) or `sudo ufw deny 174/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 174 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 174" dir=in action=allow protocol=UDP localport=174`.
What applications and services use port 174?
Port 174/UDP is used by the mailq service. Specific uses depend on the software and configuration. Check our related tools section for more information.