Securing a cellphone account

[MichaelRSorg]

Just an FYI. There is more info/links about securing a cellphone account in the Sim Swap section of DefensiveComputingChecklist.com

 

[Ralph]

I've run a VPN on my cell phone for a while now, periodically letting it reconnect to a different country- why not? I got to wondering since the cell connection is used for much of the actual data transfer, is the VPN really doing much good. I had the idea to turn off the cell connection and force things through wifi where it will be forced through the VPN. Would this be more secure than leaving cell data active? Of cause doing that requires having a wifi connection, but my cell phone rarely leaves the house. Also, I wouldn't leave the cell data permanently disabled, although I probably could. Any ideas about wifi with VPN vs cell data security?

 

[SeanBZA]

VPN means the cell carrier has no idea, other than the amount of data, and where it is going and coming from, to use. Thus they cannot use DNS spoofing or redirection to point you to adverts or landing pages they control, and thus no way to get more money from you other than the money you pay for the big dumb pipe of data. Does at least get rid of that, and you can just use a VPN inside the country you live in, as that will be the fastest, and also will not allow the cell carrier to throttle on a per application basis, like a lot of them do. It turns the link from your phone, to them, into a long dumb ethernet cable, stripping most of the redirection and caching away that is so common on cellular connections.

 

[Ralph]

Thanks for that info. I was under the (wrong) impression the cell phone VPN would protect the wifi portion but not cellular data.

 

[Tazz]

You can test this yourself to confirm that it is working correctly.
I use Network Analyzer, but I'm sure there are other apps that do the same thing.

The "Info" page shows your ip address, dns server, gateway, external ip address and more. With your cellphone only connected to cellular data reload the "External IP" line, note the address. Then start your VPN. Go back to Network Analyzer and reload the "External Ip" line. The address should change to the VPN address.

 

[Ralph]

I'll give that a try, thank you.

 

[CSPea]

Or - with your VPN App running - connect to ShieldsUp and trigger an open-ports test - once with and once without your WiFi enabled, and note the IP address each time of the VPN 'exit' server that's being tested by each of the ShieldsUp sessions.

I'll predict from my own recent tests that ShieldsUp will 'see' the exact same VPN server IP address each time, whether your phone is using cell data only, or WiFi.

Note that your VPN App will likely auto-close each time you change your phone's network settings, so, for consistency simply choose the same VPN exit server (the same 'Country') when you relaunch your VPN App for the second part of this test.

(Also I'll assume your VPN service won't have switched between its possibly multiple exit servers when you run your second test!)

You might also be interested in the small sub-set of open ports that ShieldsUp reveals on (any of) your VPN's 'exit' servers ... but that would be a whole other discussion.

 

[Ralph]

Another good test, thanks. I didn't think of ShieldsUp. I do have a profile on the VPN that has a fixed exit server. One or two sites kept saying I was using an unrecognized device (on my laptop) almost every login and annoying me with email verifications and captchas (sp). I know from a security view it's good they do that, but not to me. With rare exception I let the VPN pick random exits. I'll give ShieldsUp a try later and see what it says. Thanks again.

 

[EdwinG]

I would use https://test-IPv6.com and check what IPvX addresses/carriers it would detect. If I’m on VPN, it should match my VPN providers.

 

[AlanD]

A VPN can certainly be used with cellular data. My phone supplier, by default, routes traffic via a DNS server which blocks various types of sites, e.g. adult sites, despite me being registered as over 18.

Installing a VPN on the phone lets me use a different DNS and get to any site that I want via cellular data.

 

[Ralph]

Looks like my VPN (Proton) does what it is supposed to on my phone. Especially now days it's a good idea to check things, especially security wise, rather than assuming all is OK.