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Android wallpaper images can threaten privacy

fingerprintjs.com

21–30 of 81 posts

Re: Android wallpaper images can threaten privacy

#21

It's not constant. I expect that people change wallpaper frequently.

Unfortunately, constancy is irrelevant. If a malicious app is using this API to locate you, it can detect when your wallpaper changes and use its app_id (unchanged) plus wallpaper fingerprint (changed) to phone home with "Yo, this user's wallpaper thumprint is now Y."

Re: Android wallpaper images can threaten privacy

#24
post #7

Although this is an interesting, novel method, there are so many fingerprinting capable APIs in native code that I don't think this matters much. Many apps I use daily require internal storage permissions and a bunch of them drop random dotfiles with magical IDs in there. Xiaomi even dumps a world readable unique device ID on the emulated SD card. Not all apps require external storage permissions, but even then there…

Google is trying their absolute hardest to reduce the fingerprinting surface

Really? If true, it's so they will be the only source of such tracking info.

Google is like the one eye, it never stops seeking, looking, tracking you.

Re: Android wallpaper images can threaten privacy

#26

how am I being tracked from this? It takes pages to get to the point where supposedly the wallpaper color reduction could be unique enough ....but when is that going to be used to track me? Or rather, who is going to depend on that to track me across the device? Stretch no?

Color theme is generated from Wallpaper.

Color theme consists of at least 3 colors taken from the wallpaper.

At least 3 unique colors is enough to make the user potentially uniquely identifiable, depending on how rare the color combos are.

2²⁴ (R⁸G⁸B⁸) combinations for every color times 3 colors means 2⁷² combinations.

And there are color samples taken from potentially two different wallpapers.

Other apps have access to the colors picked for the theme generated from the wallpaper so they can theme themselves accordingly.

This means an app can use your color theme (of 3 or 6 colors) as a nearly unique fingerprint. The odds of collision for smaller apps (sub 1 million downloads) are pretty damn low.

Re: Android wallpaper images can threaten privacy

#28

It's not constant. I expect that people change wallpaper frequently.

It's been more than a year since I last changed my wallpaper.

I've used the same wallpaper on every computing device I've owned, for the last 26 years.

Re: Android wallpaper images can threaten privacy

#29
post #24
post #7

Although this is an interesting, novel method, there are so many fingerprinting capable APIs in native code that I don't think this matters much. Many apps I use daily require internal storage permissions and a bunch of them drop random dotfiles with magical IDs in there. Xiaomi even dumps a world readable unique device ID on the emulated SD card. Not all apps require external storage permissions, but even then there…

Google is trying their absolute hardest to reduce the fingerprinting surface Really? If true, it's so they will be the only source of such tracking info. Google is like the one eye, it never stops seeking, looking, tracking you.

> If true, it's so they will be the only source of such tracking info.

So... they're reducing their competition? Sounds anti-competitive. They wouldn't know anything about that though.

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