Why do you assume a "basic phone" would protect you in any way? It's far more likely to only be capable of insecure, easily interceptable forms of communication (e.g. SMS). Also, it's software is likely much worse than more popular phones (e.g. an egregious example is cheap Android phones shipping with malware preinstalled).
A WiFi access point has far less capability to hack its clients than a baseband firmware on an LTE modem with direct memory access to the host.
This is basic opsec stuff. If you’re interested it is a cool rabbit hole to go down just to see how insecure standard systems are.
Maybe because I’m not opsec and don’t know my ass from a hole in the ground, but my security recommendation would be, no, do not purposely connect your machine to a known compromised system regardless of its advertised purpose, attack vectors, attack surface, probability of unwanted exploitation, or justification as to why it’s necessary to do so, because you’re exposing yourself, and possibly corporate machine and network, to compromise. Find a trusted system (aka audited and considered reasonably low risk while acknowledging no system can ever be deemed fully secure and trust, or zero trust is a large determining factor) and consider the compromised machine as not existing at all, therefore not being an option at all, because connecting to it would go against common sense and 8th graders practice better security habits
Edit: yes, I guess you're concerned about sim-resident malware exploiting the modem, exploiting the rest of the machine via USB.
Also, if you're that paranoid, you should probably be running something seL4-based to better compartmentalize compromises.
/me keeps (semi-)patiently waiting for SpectrumOS... https://spectrum-os.org/
[0] https://www.extremetech.com/defense/161870-the-humble-sim-ca...
Carrying a general purpose computer of substantial complexity that is equipped with state of the art sensors, optics, and components (including ai), which is then topped with yet another thick complex layer of software, which is subject to known and unknown access (by various parties), is not the same thing as a telephone (analog, digital, wired, or not).
Today, unless in a secured EM cage, there really aren't that many places where you can be certain you can have a private conversation, face to face. Visiting friends? Alexa and friends may be listening. Even the lousy TV sets :) Walk in the park? Your companion likely has a smartphone.
A healthy society requires the availability of private spaces and private interactions. When a citizenry becomes aware of pervasive surveillance it self censors. Self censorship prevents airing of views in an unemcumberred manner. When views are constrained, problems remain unaddressed.
Tyranny typically thrives in such insecure and non-optimal circumstances.
If anything, you're making yourself more vulnerable with a basic phone over an iPhone or Android device with proper security practices.
Even then the assurance is only so high. Governments operate what are called SCIFs, Secure Compartmentalized Information Facilities, where they not only conduct physical exclusion and EM hardening but also acoustic damping so that an adversary can't, in theory, listen through the walls with a fancy stethoscope or a laser microphone.
There's a scene from Neuromancer where Molly and Case pay another character for a private discussion room, which is basically a cyberpunk SCIF. I've always found that scene oddly prescient; privacy today is quickly becoming a luxury.
Tbh the only two positives were:
- Battery would last several days on a single charge. I had totally forgotten that that used to be the case.
- Less time wasted on social media etc.
But the drawback was immense!
For one, it was not until I put my smart phone away that I realised just how valuable Google Maps is to me.
And of course, a lot of my communications with other people are in various apps these days. SMS is just not very useful at all now.
So the lesson learned was that it is better to have a smart phone.
It’s very much worse
Several days? Surely you meant weeks? Unless you spent an hour or two calling on the phone every day, of course.
I get 5-10 days out of my iPhone depending on desire for leisure. In the "dumb" era the number was about 2-3 weeks, even when I was young and always texting throughout the day.
I probably use the phone a lot more than you. My iPhone has to be charged at least twice a day, and it’s not even that old. My current iPhone is an iPhone 14 Pro.
That's what people are using iPhones for these days?
Unfortunately, even if you trust your "basic" phone to not be compromised, it still means you can't have a personal computer. From what I've read, that's the strategy used on the Kremlin - for security reasons, they banned computers and went back to typewriters.
If your phone and the phone of the other party are not compromised, it is indeed possible to conduct end-to-end encrypted calls with perfect forward secrecy.
That's something you can never rely on though.
Getting the key length up is a real challenge tho.
But WhatsApp (or… anything) would be great if it could easily share PGP coded messages scanned in via QR codes.