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Collecting huge amounts of data with WhatsApp

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Re: Collecting huge amounts of data with WhatsApp

#31

It clearly says so in the WhatsApp settings what people can and cannot see. This is the modern day equivalent of cold calling a range of home numbers and see who answers. If you don't want that information to be public, disable it. Simple as that. This functionality is pretty much what made WhatsApp so easily accessible for anyone in the first place.

If you get cold-called, you will catch on that somebody is checking your status (home/not home) or tries to elicit information from you – because you are directly involved. With this API, you'll never notice that somebody tracks you. Most non-tech people will never check the settings tab and even fewer will check the privacy settings. They are not aware they are sharing their info publicly.

Re: Collecting huge amounts of data with WhatsApp

#32
post #21

Man, my public GitHub profile ties my email address to my photograph. And that stuff is also in each of my public commits. With modern Android's anti-spam features, I can even dodge spam calls to my phone, so this is not a problem for me.

What is the point of your comment? That it isn't a problem for you so therefore it shouldn't be a problem for the remaining billion of WhatsApp users?

I went back and forth on this, but I think it's quite clear what the point of the comment is so I'm not going to explain.

Re: Collecting huge amounts of data with WhatsApp

#33
post #22

If you think there is no problem, you are wrong. The blog post does not show all the information leaks that this implies. Example: I can modify the script to monitor all the numbers I've in my phone, so that based on the online/offline status in a few weeks I can be able to guess who is having conversations together, discovering cheatings, work affairs, ... EDIT: Practical example. After collecting enough data about…

Well, maybe. I don't want to discount this concept entirely because some info is being "leaked" if that is the right word, but...

Let's say one of your contacts chats a lot because it's a chatty person. They're online far more than another person. What if that other person only chats on the bus on the way to and from work at roughly the same time every day to tell their wife they're on the way home. This activity will overlap with the chatty person's activity all the time.

By your rationale, they are having a conversation, maybe cheating, and maybe having a work affair.

I think the more contacts a user that are active, the higher probability that your model predicts they are having a "conversation" with another user. You'll probably find that your thresholds are really hard to fine-tune: maybe we say A chats with B if abs(A.activeTime - B.activeTime) super hard to find* and even harder to validate.

Sure, there is some information here (the picture probably being the most concretely weird) but the fact that you can just go to the App and check a box for privacy means that this seems like not a huge issue.

Yes, WhatsApp made the software, but its your responsibility to apply your own privacy settings.

Re: Collecting huge amounts of data with WhatsApp

#34
post #21

Man, my public GitHub profile ties my email address to my photograph. And that stuff is also in each of my public commits. With modern Android's anti-spam features, I can even dodge spam calls to my phone, so this is not a problem for me.

> With modern Android's anti-spam features, I can even dodge spam calls to my phone, so this is not a problem for me.

With those modern anti-spam features, you leak all call details to those providers. Read up their ToS.

Re: Collecting huge amounts of data with WhatsApp

#35
post #33
post #22

If you think there is no problem, you are wrong. The blog post does not show all the information leaks that this implies. Example: I can modify the script to monitor all the numbers I've in my phone, so that based on the online/offline status in a few weeks I can be able to guess who is having conversations together, discovering cheatings, work affairs, ... EDIT: Practical example. After collecting enough data about…

Well, maybe. I don't want to discount this concept entirely because some info is being "leaked" if that is the right word, but... Let's say one of your contacts chats a lot because it's a chatty person. They're online far more than another person. What if that other person only chats on the bus on the way to and from work at roughly the same time every day to tell their wife they're on the way home. This activity wil…

If you check the model I described in my comment, it should filter the "bus problem", since it will detect a chat only if, compared to the standard "bus time" probability of the user A chatting, it is chatting more if in the same range also B is chatting. If you add to this that people on Whatsapp usually do not talk to the exact minutes, it is definitely possible to create a robust system for guessing with good probability of two have often conversations. Also note that the phone numbers in input are not random, are the ones of a connected circle of persons. Add to this the fact that we can split the ranges even, potentially, by few minutes, and you can even detect interesting stuff for people having continuos chats with multiple persons like teenagers. Another thing that is possible probably is also "groups detection", since at new messages a set of users will activate at the same time.

Re: Collecting huge amounts of data with WhatsApp

#37
post #21

Man, my public GitHub profile ties my email address to my photograph. And that stuff is also in each of my public commits. With modern Android's anti-spam features, I can even dodge spam calls to my phone, so this is not a problem for me.

> With modern Android's anti-spam features, I can even dodge spam calls to my phone, so this is not a problem for me. With those modern anti-spam features, you leak all call details to those providers. Read up their ToS.

I have t mobile. Sometimes I get calls labeled "scam likely".

https://support.t-mobile.com/thread/139000

I'd like to know more about the anti spam features. Right now, my anti spam tactic is if an incoming call doesn't start Google voice saying "to accept press one", it is likely something I don't care for.

Re: Collecting huge amounts of data with WhatsApp

#38

Just checked if I was affected and happily I found I'd set every possible setting to private or disabled. I figure five eyes already had this information. I think they would have tools to decrypt all communications from any app, by using rooted phones that scan their own memory for common crypto libraries and then extract the keys. On the initial run it would not know where to look, and the phone would be set up to g…

You are affected: There's no way to disable the "online" status display when the app is opened in WhatsApp.

Re: Collecting huge amounts of data with WhatsApp

#39

It clearly says so in the WhatsApp settings what people can and cannot see. This is the modern day equivalent of cold calling a range of home numbers and see who answers. If you don't want that information to be public, disable it. Simple as that. This functionality is pretty much what made WhatsApp so easily accessible for anyone in the first place.

You can't disable the "online" status display when you're active in WhatsApp. Their settings page doesn't indicate this. So it's still possible to profile your contacts even with everything set to "maximum privacy".

Re: Collecting huge amounts of data with WhatsApp

#40
post #33
post #22

If you think there is no problem, you are wrong. The blog post does not show all the information leaks that this implies. Example: I can modify the script to monitor all the numbers I've in my phone, so that based on the online/offline status in a few weeks I can be able to guess who is having conversations together, discovering cheatings, work affairs, ... EDIT: Practical example. After collecting enough data about…

Well, maybe. I don't want to discount this concept entirely because some info is being "leaked" if that is the right word, but... Let's say one of your contacts chats a lot because it's a chatty person. They're online far more than another person. What if that other person only chats on the bus on the way to and from work at roughly the same time every day to tell their wife they're on the way home. This activity wil…

> Yes, WhatsApp made the software, but its your responsibility to apply your own privacy settings.

I do get Caveat Emptor but a lot of people do not understand the meaningful implications of privacy.

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