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Posted4 months agoActive3 months ago
Ask HN: Can I use grapheneos or flx1 Linux phone to prevent cell tower hacking?
cell phone securityGrapheneOSLinux phone
Ask HN: Can I use grapheneos or flx1 Linux phone to prevent cell tower hacking?
No synthesized answer yet. Check the discussion below.
Discussion (5 comments)
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You aren't allowed to control the software running on the baseband or SIM card, even with GrapheneOS on Pixel, or FLX1. With the PinePhone you can control the ARM processor within the baseband, but you can't control the Hexagon processor.
Fascinating comment. I clicked that link and don't see anything in that readme regarding baseband. I'm very interested to understand more about that term. I was not aware that a SIM is actually executing code.
I had to come back and edit this comment. What about an eSIM? No physical SIM at all, so this would have baseband in software, right? Can these open source phones provide better control that way?
Here modem == baseband. The SIM is separate to the baseband. SIM cards run their own OS that can run software from carriers, look at osmocom.org research for more. An eSIM is still a physical device, just soldered onto the motherboard, but still separate to the baseband. The baseband is always software running on hardware, its just not yours to control, and very complex to reimplement even if you had control. Apple only just managed to replace Qualcomm basebands with their own version recently, and they had to make their own baseband processors to be able to do that.
Great stuff, thanks so much.
3 months ago
And, right on time, this article about baseband and the "Horribly scary SIM farm"
https://cybersect.substack.com/p/that-secret-service-sim-far...