I'm using my iPhone personal hotspot to connect to the internet on my computer via usb connection. I don't go through any other router or connection. The phone is my only means of connecting my computer to the internet. The phone is jailbroken.
I did a
nmap scan of my public IP address and it shows that port 21 is open. Everything I've ever read has said ftp is unsecure shouldn't be used. So it seems strange to find this port open on a public ip address. I don't use ftp for anything (that I'm aware of.)
$ nmap -Pn xxx.xxx.xxx.xxx --reason Nmap scan report for xxx.xxx.xxx.xxx Host is up, received user-set (0.014s latency). Not shown: 999 filtered ports Reason: 999 no-responses PORT STATE SERVICE REASON 21/tcp open ftp syn-ack Nmap done: 1 IP address (1 host up) scanned in 6.72 seconds
Is a public ip address exclusive to a single device or are there other devices in the cellular network sharing the same ip?
Is there any risk that someone could gain access to the data on my phone or computer through this open ftp port?
And if there is a risk, how would I go about closing this port?