Why is the TCP port 6666 and port 7777 open in the LTE router?
I've got a LTE wifi router(JioFi 2) and there's port 6666 and 7777 are open.
scan result,
PORT Â Â STATE SERVICE
53/tcp  open domain
80/tcp  open http
6666/tcp open Â
7777/tcp open Â
I can understand why port 53 and 80 are open, but why 6666 and 7777 ? What are they doing there ? The device is made by Haier, which is accused many times of shipping devices with preinstalled malwares.
So my main question is how can I go deeper into this issue ?
Port 7777/tcp can be used by: iChat server file transfer proxy or Oracle Cluster File System 2 or even games (Ultima Online, Active Worlds). Same for port 6666 - this one is often used for relay chat, but can indeed be used by a lot of malware too. So it's not the port itself that is the problem (or it's current state). You must analyse the traffic on that port when the device is in normal functionality mode in order to determine if there is something bad sent through there.