All ports

Port5755/UDP

openmailg

Port

5755

Protocol

UDP

Category

Registered

Service

openmailg

What is port 5755?

Port 5755/UDP is a Registered port, registered with IANA for specific applications. It is associated with the openmailg service.

OpenMail Desk Gateway server

Useful commands

nmapnmap -p 5755 -sV example.com
netcatnc -zv example.com 5755
curlcurl -v http://example.com:5755/
telnettelnet example.com 5755
bash(echo > /dev/udp/example.com/5755) 2>/dev/null

Firewall commands

UFWAllow
sudo ufw allow 5755/udp
Deny
sudo ufw deny 5755/udp
iptablesAllow
sudo iptables -A INPUT -p udp --dport 5755 -j ACCEPT
Deny
sudo iptables -D INPUT -p udp --dport 5755 -j ACCEPT
firewalldAllow
sudo firewall-cmd --permanent --add-port=5755/udp
WindowsAllow
netsh advfirewall firewall add rule name="Open Port 5755" dir=in action=allow protocol=UDP localport=5755

Security 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 5755/UDP?

Port 5755/UDP is associated with the openmailg service. OpenMail Desk Gateway server

Is it safe to expose port 5755 to the Internet?

It depends on the service and configuration. Port 5755 (openmailg) 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 5755 is open?

You can use nmap: `nmap -p 5755 -sV example.com`, netcat: `nc -zv example.com 5755`, or the bash command: `(echo > /dev/udp/example.com/5755) 2>/dev/null && echo "Open" || echo "Closed"`.

How do I open or close port 5755 on my firewall?

On Linux with UFW: `sudo ufw allow 5755/udp` (open) or `sudo ufw deny 5755/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 5755 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 5755" dir=in action=allow protocol=UDP localport=5755`.

What applications and services use port 5755?

Port 5755/UDP is used by the openmailg service. Specific uses depend on the software and configuration. Check our related tools section for more information.