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Privacy: Is That iPhone?

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Re: Privacy: Is That iPhone?

#41

Post by TurkishPoptart »

fpgaminer wrote: post #36
gorgoiler wrote: post #19

Earlier quoted context omitted.

I applied filters and took a screenshot of the screenshot to reduce image fidelity in case it contained any [covertly embedded]* identifying information [in the form of watermarks or hidden pixels] . *added for clarity.

In case people aren't aware, such a thing _is_ possible. Companies have used steganography techniques in the past to secretly embed identifiers into movies and other visual content. It's been used to track down the movie leakers, for example. Another example; most printers covertly embed an identifier in their prints. I have a vague memory of a pre-release video game doing it? Or maybe it was just debugging informati…

Sorry to nit-pick, but isn't the concept of hiding messages in images steganography, rather than stenography? studying for Security+

Re: Privacy: Is That iPhone?

#43

Post by blkhp19 »

kpU8efre7r wrote: post #20
saagarjha wrote: post #11

Earlier quoted context omitted.

Did you… print out a screenshot of your phone?!

To save a photo someone sends her, my girlfriend's mother takes a screenshot. A lot of her printed photos have battery or other information on them.

It blows my mind, and makes me nervous about my own future, that old people do this kind of thing.

Are they actually incapable of learning the right way to do things? Is neuroplasticity playing a role here? Do they not care that their images look terrible when zoomed in on? I guess they grew up in an era when photos frequently had time and date stamps, and if their eyesight is going... I guess that explains both points.

Re: Privacy: Is That iPhone?

#44

Post by saagarjha »

TurkishPoptart wrote: post #41
fpgaminer wrote: post #36

Earlier quoted context omitted.

In case people aren't aware, such a thing _is_ possible. Companies have used steganography techniques in the past to secretly embed identifiers into movies and other visual content. It's been used to track down the movie leakers, for example. Another example; most printers covertly embed an identifier in their prints. I have a vague memory of a pre-release video game doing it? Or maybe it was just debugging informati…

Sorry to nit-pick, but isn't the concept of hiding messages in images steganography, rather than stenography? studying for Security+

Yes.

Re: Privacy: Is That iPhone?

#45

Post by saagarjha »

gorgoiler wrote: post #30
kissickas wrote: post #29

Earlier quoted context omitted.

I get the filters, but why the second screenshot? Aren't you just adding more hypothetical tracking pixels with that step?

So that the final screenshot is from outside the app being screenshotted, and as a bonus you get another round of JPEG obfuscation.

Screenshots are PNGs.

Re: Privacy: Is That iPhone?

#46

Post by godelski »

> Phone users can currently disable the IDFA, but have to do so manually; Android users aren’t even given this option

This actually false. You can change your Ad ID on Android. I just looked (and checked)If you go to Settings > Privacy > Ads you can see this IDFA. At the top (it looks like a header and not an option, so I will not fully fault Mozilla because this is a dark pattern) it says "Reset advertising ID". If you press it you can see the grey "Your advertising ID" (at the bottom) change.

Additionally, there's the option "Opt out of Ads Personalization". It has the text "Instruct apps not to use your advertising ID to build profiles or show you personalized ads." I would love if someone here could clarify this for me. Is this a suggestion to apps or is this a strict and enforceable thing? As in "Hey app, you should ignore this ID that I'm handing to you" vs "Hey app, you don't get to have this ID. Sorry." Does anyone know which it is? The language suggests to me that it is the former.

Edit: This was done on a phone running Android 10

Re: Privacy: Is That iPhone?

#48

Post by mojuba »

varenc wrote: post #40

Mozilla suggests resetting the IDFA once per month...but that seems pretty trivial to workaround? If an app you used previously starts up and sees that your IDFA changed, it's easy for that app to know that the old IDFA and the new IDFA refer to the same user! This tracking is all possible because iOS gives every app on the device the same IDFA (advertising identifier [1]). They can then correlate all your activity a…

Unfortunately the majority of more or less useful or popular apps are also linked against various analytics/attribution platforms, often many of them at once. Mixpanel, Amplitude, AppsFlyer, Branch to name a few, plus Facebook and/or Google. In fact having any of the Google's or Facebook's SDKs means tracking, e.g. Maps, Login etc.

Somehow these platforms have no problem with identifying users across their client apps even without the IDFA. Maybe it's not 100% precise, but as far as I can tell these companies keep so much information about us away from our eyes, that even the big guys (G, FB) would be jealous.

Analytics is one big dark corner of the mobile business whose significance is not fully appreciated (yet).

Re: Privacy: Is That iPhone?

#49

Post by uwydr »

blkhp19 wrote: post #43
kpU8efre7r wrote: post #20

Earlier quoted context omitted.

To save a photo someone sends her, my girlfriend's mother takes a screenshot. A lot of her printed photos have battery or other information on them.

It blows my mind, and makes me nervous about my own future, that old people do this kind of thing. Are they actually incapable of learning the right way to do things? Is neuroplasticity playing a role here? Do they not care that their images look terrible when zoomed in on? I guess they grew up in an era when photos frequently had time and date stamps, and if their eyesight is going... I guess that explains both poin…

Pretty sure many apps don't even allow you to save pictures at all. Maybe Facebook is one of them, not sure. That + the button to save pictures not being at the same place on all apps makes screenshots easier and reliable. They simply work.
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