How to stay private when using Whatsapp?

Sigismund

brandy078 Not using Whatsapp so can't say if this is same but you may run into issues if trying to use other meta apps with a VPN on. Including your account being suspended.

SovereignCopper

Sigismund Not really, because with the email example you still have a choice to not send messages to Gmail addresses/not give people that mail address if you know they'll use Gmail.

I have not heard of any problems with running WhatsApp on GOS with an always-on VPN (+ block non-VPN traffic).

Delaney

SovereignCopper

People will probably save that unregistered number to their contacts under your full name, so my guess is it will still reach WhatsApp.

https://faq.whatsapp.com/1191526044909364/?locale=en_US

If any of your contacts in your device address book aren’t yet using WhatsApp, we protect their privacy by managing the phone number in a way that is designed to prevent those contacts from being identified by WhatsApp. We do this by creating a cryptographic hash value of their phone number, and then delete the number. Each cryptographic hash value is stored on WhatsApp’s servers, linked to the WhatsApp users who synced the corresponding phone numbers before they were hashed so that we can more efficiently connect you with these contacts when they join WhatsApp

So in effect, this is how WhatsApp can link unregistered numbers with WhatsApp users without actually saving their numbers, by using a shadow profile that is trivially linked to your number and full name once you sign up.

SovereignCopper

Delaney First, my guess would be that pseudonymizing is pretty much bullshit, because a hashed phone number would be easy to brute-force, considering the very limited/standardized character range and length.

Second, this doesn't apply to the question, because this person wants to use the number for WhatsApp.

neotux

brandy078 what could i do to stay as anonymous as possible and still have the maximum of privacy when using WhatsApp?

Not much or so it seems:

(Warning: YT video ahead) https://youtu.be/33Cm88Dazoo

https://news.bloomberglaw.com/esg/ousted-whatsapp-security-head-sues-meta-after-whistleblowing

Delaney

SovereignCopper I'm not sure why you're arguing with me when the point of my response is to back up your assumption.

cupcake-alibi

I believe WhatsApp supports usernames, similar to Signal. I'm not sure, but if WhatsApp's implementation is the same as Signal's, then you should be able to hide your phone number from your contacts.

fph

cupcake-alibi This protects OP's privacy only from other fellow users though; it does not hide any information from Meta.

SovereignCopper

Delaney I think it's because we have a different understanding of what the topic starter meant by "unregistered phone number". I assumed it meant that their name wasn't linked to it via a contract, your post is about "not registered to a WhatsApp account". AFAIK it is still not possible to register a WhatsApp account without a phone number, but there was talk about the introduction of usernames some months ago, but AFAIK that's still in beta and I doubt that it will hide your number from Meta, but it will be useful towards other users.

NetRunner88

When you call with WhatsApp you can't avoid to give the phone permission, and therefore meta grab your sim identifiers (phone number)

brandy078

NetRunner88 But without calling with WA, they don't get my sim identifiers? Or is necessary to give WA that permission?

SovereignCopper

NetRunner88 That is after you registered for an account... using your phone number.

NetRunner88

brandy078
You can avoid it but you will not be able to call or receive a call

NetRunner88

SovereignCopper
I know but it is worth knowing