4 ms·

In theory this is meant to be one of the advantages of end to end encryption: no more "accidental" leakage of user data between users, leakage in logs, etc (rem

by est31 4y ago

In theory this is meant to be one of the advantages of end to end encryption: no more "accidental" leakage of user data between users, leakage in logs, etc (remember Facebook's logging incident? [0]). as it's only available on end user devices. And if you look at Apple's documentation [1], they say that iCloud is end to end encrypted. This is obviously not accurate as Apple keeps decryption keys for themselves. But this issue is even worse: here, the end to end encryption was circumvented in such a bad way that this bug could surface. [0]: https://krebsonsecurity.com/2019/03/facebook-stored-hundreds-of-millions-of-user-passwords-in-plain-text-for-years/ https://krebsonsecurity.com/2019/03/facebook-stored-hundreds... [1]: https://support.apple.com/en-us/HT202303 https://support.apple.com/en-us/HT202303

sneak 4y ago
Apple does not claim that iCloud photos are end to end encrypted. https://support.apple.com/en-us/HT202303 https://support.apple.com/en-us/HT202303 https://www.reuters.com/article/us-apple-fbi-icloud-exclusive/exclusive-apple-dropped-plan-for-encrypting-backups-after-fbi-complained-sources-idUSKBN1ZK1CT https://www.reuters.com/article/us-apple-fbi-icloud-exclusiv...
- est31 4y ago
  Good point about that. Makes sense then how this issue could surface.
  - MBCook 4y ago
    They were going to, but some people flipped out about “their devices spying on them”. So instead photos are unencrypted and still scanned server-side.
    - trifurcate 4y ago
      Do you have any statement from Apple themselves or any indication that this was their line of thought? As far as I know, the on-device iMessage image scanning for CSAM (presumably what you are referring to) is a shipped feature live on all recent iOS builds, and I don't ever recall seeing any sort of public debate regarding whether iCloud photos should be encrypted or not (to be fair, before this thread, I assumed that they were).
      - fragmede 4y ago
        They shipped a version with a reduced feature set that does not include any off device notification. https://www.apple.com/child-safety/ https://www.apple.com/child-safety/
- johnnyAghands 4y ago
  Makes sense, good set of training data :)
- MichaelCollins 4y ago
  Right, they say iMessage is end-to-end encrypted, but this is only true if you and the people you talk to don't use iCloud backups. If you do, then iMessage's E2E encryption silently degrades to key escrow.
  - dmix 4y ago
    I've read that Apple could technically inject a 3rd key in a two party chat and eavesdrop on it. Not sure how true that is in practice, but it seems plausible based on their security design document.
    - jonny_eh 4y ago
      They could do anything on their phones.
      - saurik 4y ago
        Sure, but some things don't require a malicious software update.
      - TimTheTinker 4y ago
        So could literally anyone who writes and distributes end-point software that encrypts and/or decrypts content (or hosts software that does) - including operating systems, browsers, e2e messaging apps, password managers, VPN clients, etc. I believe solving this problem is the crux of the next major breakthrough (if it ever comes) in privacy and personal security. I'm not even sure a solution exists, but a lot can happen when smart people put their heads together on a seemingly intractable problem.
    - skrowl 4y ago
      This is true. It's been proven to have happened in multiple court cases. They can basically insert another "end" for the end to end encryption without any of the parties knowing. You basically should never trust Apple / Google / Microsoft / Amazon / etc to handle your private information... ever. Use audited open-source messaging apps.
- conradev 4y ago
  One thing to remember is that end-to-end encryption comes with the very real possibility of complete and total loss of data, which is hard to stomach for someone’s entire photo library. iMessage is end-to-end encrypted, but a key to decrypt messages is stored in iCloud backups.
  - modeless 4y ago
    Your statement is nonsensical. Either Apple has the key, or it's end to end encrypted. Both cannot be true. And in fact Apple has the key, even if you turned off iCloud backups in most cases since the person you're talking to probably has it enabled. Which makes the marketing misleading at best, and downright fraudulent at worst. BTW both Apple and Google have a way of doing end to end encryption of backups with a recovery option in the case of device loss. Apple deliberately chooses not to enable it for iMessage and iCloud photos (it is used for keychain passwords among other things). Credible news reports state that Apple did this at the explicit request of the FBI. https://www.reuters.com/article/us-apple-fbi-icloud-exclusive/exclusive-apple-dropped-plan-for-encrypting-backups-after-fbi-complained-sources-idUSKBN1ZK1CT https://www.reuters.com/article/us-apple-fbi-icloud-exclusiv... Also note that Apple policies prohibit anyone else from offering cloud backups for iPhones, so you're SOL if you want cloud backups and privacy. Apple's way or the highway.
    - sneak 4y ago
      > Credible news reports state that Apple did this at the explicit request of the FBI. A minor point of fact (I have posted this Reuters link more than anyone): a careful reading of the article does not specify an explicit request. It is very much implicit in the article. There is no direct reporting on the request itself. It is obvious that there was an explicit request. The article simply strongly implies it, because Reuters will not report as fact things they can not verify.
    - conradev 4y ago
      Yes, I apologize for using the incorrect label. iMessage is not end-to-end encrypted for most people. The point I was trying to make still stands. The recovery options are a form of key escrow. They require a recovery code. As I'm sure you know, if you lose your device and forget the recovery code, then it's total loss – the HSM will reset after a fixed number of tries. People are plenty capable of doing that, and with a billion devices, some non-trivial number of them do it regularly.
deleted 4y ago
[deleted]

by est31 4y ago

sneak 4y ago

Apple does not claim that iCloud photos are end to end encrypted. https://support.apple.com/en-us/HT202303 https://support.apple.com/en-us/HT202303 https://www.reuters.com/article/us-apple-fbi-icloud-exclusive/exclusive-apple-dropped-plan-for-encrypting-backups-after-fbi-complained-sources-idUSKBN1ZK1CT https://www.reuters.com/article/us-apple-fbi-icloud-exclusiv...

est31 4y ago
Good point about that. Makes sense then how this issue could surface.
- MBCook 4y ago
  They were going to, but some people flipped out about “their devices spying on them”. So instead photos are unencrypted and still scanned server-side.
  - trifurcate 4y ago
    Do you have any statement from Apple themselves or any indication that this was their line of thought? As far as I know, the on-device iMessage image scanning for CSAM (presumably what you are referring to) is a shipped feature live on all recent iOS builds, and I don't ever recall seeing any sort of public debate regarding whether iCloud photos should be encrypted or not (to be fair, before this thread, I assumed that they were).
    - fragmede 4y ago
      They shipped a version with a reduced feature set that does not include any off device notification. https://www.apple.com/child-safety/ https://www.apple.com/child-safety/
johnnyAghands 4y ago
Makes sense, good set of training data :)
MichaelCollins 4y ago
Right, they say iMessage is end-to-end encrypted, but this is only true if you and the people you talk to don't use iCloud backups. If you do, then iMessage's E2E encryption silently degrades to key escrow.
- dmix 4y ago
  I've read that Apple could technically inject a 3rd key in a two party chat and eavesdrop on it. Not sure how true that is in practice, but it seems plausible based on their security design document.
  - jonny_eh 4y ago
    They could do anything on their phones.
    - saurik 4y ago
      Sure, but some things don't require a malicious software update.
    - TimTheTinker 4y ago
      So could literally anyone who writes and distributes end-point software that encrypts and/or decrypts content (or hosts software that does) - including operating systems, browsers, e2e messaging apps, password managers, VPN clients, etc. I believe solving this problem is the crux of the next major breakthrough (if it ever comes) in privacy and personal security. I'm not even sure a solution exists, but a lot can happen when smart people put their heads together on a seemingly intractable problem.
  - skrowl 4y ago
    This is true. It's been proven to have happened in multiple court cases. They can basically insert another "end" for the end to end encryption without any of the parties knowing. You basically should never trust Apple / Google / Microsoft / Amazon / etc to handle your private information... ever. Use audited open-source messaging apps.
conradev 4y ago
One thing to remember is that end-to-end encryption comes with the very real possibility of complete and total loss of data, which is hard to stomach for someone’s entire photo library. iMessage is end-to-end encrypted, but a key to decrypt messages is stored in iCloud backups.
- modeless 4y ago
  Your statement is nonsensical. Either Apple has the key, or it's end to end encrypted. Both cannot be true. And in fact Apple has the key, even if you turned off iCloud backups in most cases since the person you're talking to probably has it enabled. Which makes the marketing misleading at best, and downright fraudulent at worst. BTW both Apple and Google have a way of doing end to end encryption of backups with a recovery option in the case of device loss. Apple deliberately chooses not to enable it for iMessage and iCloud photos (it is used for keychain passwords among other things). Credible news reports state that Apple did this at the explicit request of the FBI. https://www.reuters.com/article/us-apple-fbi-icloud-exclusive/exclusive-apple-dropped-plan-for-encrypting-backups-after-fbi-complained-sources-idUSKBN1ZK1CT https://www.reuters.com/article/us-apple-fbi-icloud-exclusiv... Also note that Apple policies prohibit anyone else from offering cloud backups for iPhones, so you're SOL if you want cloud backups and privacy. Apple's way or the highway.
  - sneak 4y ago
    > Credible news reports state that Apple did this at the explicit request of the FBI. A minor point of fact (I have posted this Reuters link more than anyone): a careful reading of the article does not specify an explicit request. It is very much implicit in the article. There is no direct reporting on the request itself. It is obvious that there was an explicit request. The article simply strongly implies it, because Reuters will not report as fact things they can not verify.
  - conradev 4y ago
    Yes, I apologize for using the incorrect label. iMessage is not end-to-end encrypted for most people. The point I was trying to make still stands. The recovery options are a form of key escrow. They require a recovery code. As I'm sure you know, if you lose your device and forget the recovery code, then it's total loss – the HSM will reset after a fixed number of tries. People are plenty capable of doing that, and with a billion devices, some non-trivial number of them do it regularly.

deleted 4y ago

[deleted]