4 ms·

I don't understand the claim that this system improves their ability to detect anything. If it's really true that the system only works on data uploaded to iclo

I don't understand the claim that this system improves their ability to detect anything. If it's really true that the system only works on data uploaded to icloud then apple could have easily just done all the scanning in the cloud, because icloud is not end-to-end encrypted. In that case, all this feature does is move the computational cost of scanning from Apple's datacenters to Apple's users, saving Apple money and costing users battery life. It doesn't change anything about how effective the scanning can be. Unless I misunderstand how it works.

aoetalks 5y ago
I must have the same misunderstanding. I don’t know why this has to be device side for iCloud photos..
- dannyw 5y ago
  Because security researchers imply Apple eventually plan to turn this on for all local photos, even with icloud turned off.
  - stjohnswarts 5y ago
    all local files is what I predict.
- ziml77 5y ago
  Maybe because they plan on enabling E2EE for iCloud. Of course that's not necessarily useful given that the set of images yours are being checked against is completely opaque.
pseudalopex 5y ago
Photos are encrypted in Apple's technical summary.[1] [1] https://www.apple.com/child-safety/pdf/CSAM_Detection_Technical_Summary.pdf https://www.apple.com/child-safety/pdf/CSAM_Detection_Techni...
- modeless 5y ago
  Photos in iCloud photos are "encrypted". They are not end-to-end encrypted. Apple retains the keys. Apple can and does decrypt the photos for various purposes including for law enforcement. The encryption poses no obstacle to scanning the photos in the cloud.
- davidcbc 5y ago
  According to Apple's docs photos are encrypted in transit and on server but not end to end encrypted https://support.apple.com/en-us/HT202303 https://support.apple.com/en-us/HT202303
  - pseudalopex 5y ago
    The technical summary describes a new system where Apple just has keys for suspect images.
    - davidcbc 5y ago
      They just have keys for the safety voucher for the suspect images. It's not entirely clear that the payload in the safety voucher is the only copy of the image or if this CSAM system is in addition to what happens today.
    - modeless 5y ago
      The technical summary describes the detection system, not the rest of the product. The rest of iCloud photos is not end-to-end encrypted. If Apple was planning to introduce end-to-end encryption for iCloud photos then they should have announced it at the same time.
      - davidcbc 5y ago
        If they are using this to introduce something closer to end-to-end encryption then it seems like a clear win for users. Today photos are not end-to-end encrypted, there is nothing preventing Apple from decrypting your photos if they want (or if they are asked by law enforcement). If a part of this implementation is to make it so only the user keys OR the CSAM keys in the case of a match are able to decrypt the photos then that is a clear step in the right direction over the current system. It's not real end-to-end encryption, but it still prevents Apple from just decrypting your photos without probable cause of a very specific crime. If that is the case they should have made it a lot clearer in the initial announcement though.
dotBen 5y ago
Respectfully you've missed what this is. This has nothing to do with data sent up to iCloud - at that point not only can those photos be checked via hash they can be further reviewed if there is a positive/high degree match The issue is that this mechanism applies to photos (/data) on the local device that wouldn't otherwise make its way up to iCloud.
- Thorrez 5y ago
  Do you have a source that this is being used on all photos on the device? The EFF posts says it applies to 2 cases: photos being uploaded to iCloud, and photos through iMessage if the account holder is a child and the feature hasn't been disabled. https://www.eff.org/deeplinks/2021/08/apples-plan-think-different-about-encryption-opens-backdoor-your-private-life https://www.eff.org/deeplinks/2021/08/apples-plan-think-diff... You're right that only scanning photos uploaded to iCloud is currently pointless. But maybe Apple plans to do semi-end-to-end encryption on iCloud photos in the future, and then this feature would be useful.
  - ziml77 5y ago
    I believe it's inaccurate to lump the iMessage and iCloud scanning together. The iMessage scanning tries to classify images as sexually explicit. The iCloud scanning tries to identify images that exist in the CSAM database, accounting for recompression and cropping.
- modeless 5y ago
  No, that's what people are afraid will happen, not what's happening now. Apple has been very explicit in saying this only affects uploaded photos. For now.

aoetalks 5y ago

I must have the same misunderstanding. I don’t know why this has to be device side for iCloud photos..

dannyw 5y ago
Because security researchers imply Apple eventually plan to turn this on for all local photos, even with icloud turned off.
- stjohnswarts 5y ago
  all local files is what I predict.
ziml77 5y ago
Maybe because they plan on enabling E2EE for iCloud. Of course that's not necessarily useful given that the set of images yours are being checked against is completely opaque.

pseudalopex 5y ago

Photos are encrypted in Apple's technical summary.[1] [1] https://www.apple.com/child-safety/pdf/CSAM_Detection_Technical_Summary.pdf https://www.apple.com/child-safety/pdf/CSAM_Detection_Techni...

modeless 5y ago
Photos in iCloud photos are "encrypted". They are not end-to-end encrypted. Apple retains the keys. Apple can and does decrypt the photos for various purposes including for law enforcement. The encryption poses no obstacle to scanning the photos in the cloud.
davidcbc 5y ago
According to Apple's docs photos are encrypted in transit and on server but not end to end encrypted https://support.apple.com/en-us/HT202303 https://support.apple.com/en-us/HT202303
- pseudalopex 5y ago
  The technical summary describes a new system where Apple just has keys for suspect images.
  - davidcbc 5y ago
    They just have keys for the safety voucher for the suspect images. It's not entirely clear that the payload in the safety voucher is the only copy of the image or if this CSAM system is in addition to what happens today.
  - modeless 5y ago
    The technical summary describes the detection system, not the rest of the product. The rest of iCloud photos is not end-to-end encrypted. If Apple was planning to introduce end-to-end encryption for iCloud photos then they should have announced it at the same time.
    - davidcbc 5y ago
      If they are using this to introduce something closer to end-to-end encryption then it seems like a clear win for users. Today photos are not end-to-end encrypted, there is nothing preventing Apple from decrypting your photos if they want (or if they are asked by law enforcement). If a part of this implementation is to make it so only the user keys OR the CSAM keys in the case of a match are able to decrypt the photos then that is a clear step in the right direction over the current system. It's not real end-to-end encryption, but it still prevents Apple from just decrypting your photos without probable cause of a very specific crime. If that is the case they should have made it a lot clearer in the initial announcement though.

dotBen 5y ago

Respectfully you've missed what this is. This has nothing to do with data sent up to iCloud - at that point not only can those photos be checked via hash they can be further reviewed if there is a positive/high degree match The issue is that this mechanism applies to photos (/data) on the local device that wouldn't otherwise make its way up to iCloud.

Thorrez 5y ago
Do you have a source that this is being used on all photos on the device? The EFF posts says it applies to 2 cases: photos being uploaded to iCloud, and photos through iMessage if the account holder is a child and the feature hasn't been disabled. https://www.eff.org/deeplinks/2021/08/apples-plan-think-different-about-encryption-opens-backdoor-your-private-life https://www.eff.org/deeplinks/2021/08/apples-plan-think-diff... You're right that only scanning photos uploaded to iCloud is currently pointless. But maybe Apple plans to do semi-end-to-end encryption on iCloud photos in the future, and then this feature would be useful.
- ziml77 5y ago
  I believe it's inaccurate to lump the iMessage and iCloud scanning together. The iMessage scanning tries to classify images as sexually explicit. The iCloud scanning tries to identify images that exist in the CSAM database, accounting for recompression and cropping.
modeless 5y ago
No, that's what people are afraid will happen, not what's happening now. Apple has been very explicit in saying this only affects uploaded photos. For now.