App access to phone number

DeletedUser471

Is there anyway to hide phone number from app globally / per app / per profile? That's privacy nightmare over there.

mmobder

DeletedUser471

over where exactly?

userofgos

DeletedUser471 only apps with the Phone permission can access your phone number.

I'd suggest reading the GrapheneOS website FAQ: https://grapheneos.org/faq#hardware-identifiers

DeletedUser471

mmobder its in the grapheneos secondary profile without gplays.

DeletedUser471

userofgos so how app knew that im in specific region when there were no phone access, different region in profile, and no ip/dns leackage? it knew for sure, it even showed country phone code. if i remember correctly, last time i encountered that issue i took sim of and it worked, but now its esim so i didnt reproduce.

userofgos

DeletedUser471 so how app knew that im in specific region when there were no phone access, different region in profile, and no ip/dns leackage?

Again, this is explained on the GrapheneOS website FAQ which I previously linked to userofgos

Examples of the global OS configuration available to apps are time zone, network country code and other similar global settings. Per-profile examples are dark mode and language. Similar to extension and browser configuration / state being fingerprinted by web sites, an app could use a combination of these things in an attempt to identify the installation. All of these things vary at runtime and can be changed, but some are fairly unlikely to change in practice after the initial setup of the device such as the ones listed above. GrapheneOS will likely add further restrictions in this area and a couple toggles for certain cases like time zones to use a standard value instead.

DeletedUser471 it knew for sure, it even showed country phone code.

Try turning on Airplane mode and see if it still shows.

n3t_admin

DeletedUser471 apps can still read your region when you have a SIM installed. That doesn't mean they can read your phone number.

DeletedUser471

userofgos Yes, I did enable airplain mode back than for sure because I knew from previous experience that it can indeed see region by number and with esim - airplain mode was the only choice.

DeletedUser471

n3t_admin thx for clarification. that means post title is incorrect. I'd like them to not be able to know it, because it makes no sense to spoof region in GOS + vpn.

mmobder

DeletedUser471 it's s stupid take, buy data-only sim from global providers if your threat model is like that, and finally, RTFM

DeletedUser471

mmobder you mean my take or yours? :) I mean I just want it to be disconnected from that identifier.

DeletedUser471

mmobder yeah, my threat model is kinda cutting edge, so I'm writing that manual, not reading it.

mmobder

DeletedUser471 so I'm writing that manual, not reading it.

if that's the case, you should preach, not ask. enlight us)

DeletedUser495

mmobder using two network enabled Google apps and expecting they aren't going to see each other, that is what I call cutting edge threat model

--> https://discuss.grapheneos.org/d/27131-disable-inter-process-communication-ipc/7

DeletedUser471

mmobder that was /s, brother. i don't think i'm smartest in this community so i'd better be silent and ask what i need to evolve my knowledge.

DeletedUser471

DeletedUser495 i don't use them, i prefer tuta for push notifcations + offline osm. if i'd need gmaps for something, i'd open it via private tab without jit. if i'd intall them - i'd install them on secondary profile and not expect they don't leak through booble cloud in-built telemetrics even if they'd be on separate secondary profiles in gos, hah

DeletedUser495

DeletedUser471 security and privacy is a journey on which we all have a lot to learn. Please keep going. Chew properly every word before you let it out. All the best in your undertakings.

DeletedUser471

DeletedUser495 are you talking about "writing manual" - that was an answer to RTFM - which i disliked. thx, you too, have a nice one.

However my issue is still there - an app knows region by reading it from sim even with airplain mode.

DeletedUser495

DeletedUser471 without giving us further info about what app and under what circumstances is accessing your country code all I can tell you, sim card is not the only way of obtaining hints or your actual location information. Use of Wi-Fi, GPS and certain global settings of your device can aid this process. But you don't mention any of that.

DeletedUser471

DeletedUser495 gps/glonass disabled, wifi access disabled via wifi control special access, block connections without vpn enabled, local traffic disallowed via vpn app, timezone is set via utc offsett, not region, there is nothing more to tighten. it knows region via sim, as mentioned previouly "apps can still read your region when you have a SIM installed. That doesn't mean they can read your phone number."

DeletedUser495

DeletedUser471 I am really confused now. What purpose does your app serve when it is offline, since you have eliminated any form of network access, yet it feels it needs to access your country code for unspecific reason. I struggle to understand what your actual problem is and unless you properly explain it, I am afraid there is no helping you.