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If Mallory gets a lawful citizen Bob to download a completely innocuous looking but perceptual-CSAM-hash-matching image to his phone, what happens to Bob? I ima

If Mallory gets a lawful citizen Bob to download a completely innocuous looking but perceptual-CSAM-hash-matching image to his phone, what happens to Bob? I imagine the following options: - Apple sends Bob’s info to law enforcement; Bob is swatted or his life is destroyed in some other way. Worst, but most likely outcome. - An Apple employee (or an outsourced contractor) reviews the photo, comparing it to CSAM source image sample used for the hash. Only if the image matches according to human vision, Bob is swatted. This requires there to be some sort of database of CSAM source images, which strikes me as unlikely. - An Apple employee or a contractor reviews the image for abuse without comparing it to CSAM source, using own subjective judgement. Better, but implies Apple employees could technically SWAT Apple users.

bitexploder 5y ago
Do we know that they are using perceptual hashing? I am curious about the details of the hash database they are comparing against, but I assumed perceptual hashing would be pretty fraught with edge cases and false positives. e: It is definitely not a strict/cryptographic hash algorithm: "Apple says NeuralHash tries to ensure that identical and visually similar images — such as cropped or edited images — result in the same hash." They are calling it "NeuralHash" -- https://techcrunch.com/2021/08/05/apple-icloud-photos-scanning/ https://techcrunch.com/2021/08/05/apple-icloud-photos-scanni...
deleted 5y ago
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anonuser123456 5y ago
Downloading an image to your phone is different than uploading it to iCloud. Downloaded images are not uploaded to iCloud w/out user intervention.
- strogonoff 5y ago
  Presuming iCloud Photos is enabled by Bob, an unsuspecting citizen, all downloaded images are synced to iCloud either right away or next time on Wi-Fi, depending on settings.
  - pzo 5y ago
    True. On top of that People should now start worrying if some person on whatsapp/telegram group will share some illegal file. I have been part of few public hiking/travelling whatsapp/telegram groups. Many times I mute those group because I don't want to be notified and distracted with every single message. All those photos someone share in any whatsapp group will end up in your iphone 'Recent' album automatically even if you muted some group many months ago and didn't check at all.
    - strogonoff 5y ago
      Well, at least this feature could be disabled in WhatsApp settings as far as I know. Either way, since my original post I’ve read that the way Apple does it is by reviewing the offending material in-house first before notifying any third party (like the government), meaning it wouldn’t be as easy to SWAT a random person just like that.
- 8note 5y ago
  Today, sure. That's technically very easy to change
strogonoff 5y ago
From BBC’s article: > Apple says that it will manually review each report to confirm there is a match. It can then take steps to disable a user's account and report to law enforcement. So at least it’s the last option.

bitexploder 5y ago

Do we know that they are using perceptual hashing? I am curious about the details of the hash database they are comparing against, but I assumed perceptual hashing would be pretty fraught with edge cases and false positives. e: It is definitely not a strict/cryptographic hash algorithm: "Apple says NeuralHash tries to ensure that identical and visually similar images — such as cropped or edited images — result in the same hash." They are calling it "NeuralHash" -- https://techcrunch.com/2021/08/05/apple-icloud-photos-scanning/ https://techcrunch.com/2021/08/05/apple-icloud-photos-scanni...

deleted 5y ago

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anonuser123456 5y ago

Downloading an image to your phone is different than uploading it to iCloud. Downloaded images are not uploaded to iCloud w/out user intervention.

strogonoff 5y ago
Presuming iCloud Photos is enabled by Bob, an unsuspecting citizen, all downloaded images are synced to iCloud either right away or next time on Wi-Fi, depending on settings.
- pzo 5y ago
  True. On top of that People should now start worrying if some person on whatsapp/telegram group will share some illegal file. I have been part of few public hiking/travelling whatsapp/telegram groups. Many times I mute those group because I don't want to be notified and distracted with every single message. All those photos someone share in any whatsapp group will end up in your iphone 'Recent' album automatically even if you muted some group many months ago and didn't check at all.
  - strogonoff 5y ago
    Well, at least this feature could be disabled in WhatsApp settings as far as I know. Either way, since my original post I’ve read that the way Apple does it is by reviewing the offending material in-house first before notifying any third party (like the government), meaning it wouldn’t be as easy to SWAT a random person just like that.
8note 5y ago
Today, sure. That's technically very easy to change

strogonoff 5y ago

From BBC’s article: > Apple says that it will manually review each report to confirm there is a match. It can then take steps to disable a user's account and report to law enforcement. So at least it’s the last option.