3 ms·

iMessage is backdoored? Evidence please?

sneak 6y ago
iCloud Backup backs up plaintext of all iMessages from the device to Apple, with Apple keys (non-e2e). It also includes all SMS. This is documented plainly on Apple's iCloud security overview page. The list of things that are end-to-end encrypted is listed. iCloud Backup is not in it. It's on by default on all iOS devices. Apple was to fix this by end to end encrypting iCloud device backups, and (I understand) even had an implementation, but stopped its deployment on request of the FBI to preserve access to phone contents (including iMessage/SMS history). https://www.reuters.com/article/us-apple-fbi-icloud-exclusive-idUSKBN1ZK1CT https://www.reuters.com/article/us-apple-fbi-icloud-exclusiv...
- api 6y ago
  So turn off iCloud backups?
  - sneak 6y ago
    Then your conversation plaintext gets escrowed to Apple via just Bob instead of both Alice and Bob. (Conversations are backed up twice: once by each party.) You'd need everyone you talk to to also disable iCloud Backup. This is pretty unlikely. Easier to just use Signal, where the chat history isn't included in the device backups at all.
    - saurik 6y ago
      Signal doesn't--and can't--somehow magically prevent people from backing up their messages insecurely. That they don't support being backed up by normal backup methods on iOS--including highly-secure ones--is a missing feature (and a devastating one at that: people expect to have access to their old messages) more than a security measure. Consider this: the existence of a popular tool that helps people back up their Signal messages wouldn't somehow cause it to be accurate to claim there is a "backdoor" in Signal.
      - sneak 6y ago
        If that tool shipped as part of iOS, were on by default, and silently sent the full message history plaintext to Apple (such as if Apple iCloud Backup stopped respecting the storage class of apps and just backed up EVERY FILE), I think it would be fair to call that a backdoor (in iOS). What if iCloud Backup started including in the backup a snapshot of device RAM? I think we are splitting hairs here. The desire of users for message history in backups is entirely orthogonal to whether or not iCloud Backup is a cryptographic backdoor, in the traditional "plaintext escrow" sense. Indeed, the FBI would not have torpedoed Apple's e2e encrypted device backup system if not. Really it boils down to the fact that it's on by default and the users were never asked to consent to their full chat history being transmitted to Apple effectively in the clear. I imagine most users are unaware of the fact that the FBI has warrantless access to every iMessage they have ever sent or received.
        saurik 6y ago
        Call a spade a spade: if iCloud Backup is insecure (and it is), then say iCloud Backup is insecure, not iMessage. Your stance on this is FUD because you don't respect the semantic boundaries of the systems you are discussing, and so anyone who decides to truly listen to you and internalize the things you say leaves with a broken mental model rather than an educated stance :/. Every single person who reads what you say "iMessage, now backdoored for the FBI" who decides to stop using iMessage (which wasn't even insecure to begin with) and does NOT decide to stop using iCloud Backup (which will be insecure even if the user is using Signal, along with Signal's iOS product flaw that attempts to circular file your messages, as messaging is but one of myriad things a user does on their phone) is someone you have failed by teaching them the wrong lesson.
        sneak 6y ago
        I think that iMessage is simply a feature of iOS, same as iCloud Backup. They can't be installed or used separately, they are a single atom. A single atom with message plaintext escrow enabled by default: a backdoor. By your reasoning, would "iOS is insecure" be an accurate statement?
- saurik 6y ago
  iCloud Backup being insecure does NOT mean iMessage is "backdoored": if you don't use iCloud Backup--and there is no reason to do so, as Apple (notably unlike anything Android) has a really good local way to do highly-secure backups using iTunes--my (rather firm) understanding is that, even if you turn on the iCloud iMessage sync (which is also optional: I do not have it on, for example), iMessage actually is pretty damned secure (with no key escrow). I appreciate that a lot of people--maybe most or even "almost all" people!--use iCloud Backup, but semantics matter as you present it as if iMessage is insecure, when not only the "real" but the only issue is iCloud Backups (which we should be making sure people don't use, with targeted education campaigns, as it isn't like using Signal could ever solve this issue for all of the other personal data the user had). If you want to make this kind of argument, you need to be doing it from a place of being more informed; like, you could be trying to poke at how the protocol had a weakness--found by pod2g's team--with respect to Apple's ability to inject new keys for existing chat participants, an issue I am not sure they fixed (or even could fix, as it is arguably a UI security problem... but maybe they did, as I don't always follow the blow-by-blow); but this indirect argument you make is FUD.
  - fsflover 6y ago
    > iCloud Backup being insecure does NOT mean iMessage is "backdoored" Technically not, but in practice it is for the most users.
fsflover 6y ago
Without the source code, you should provide evidence that it's not backdoored. Given how large Apple is, how big its userbase, I am sure all agencies do everything possible to get the precious data.

iCloud Backup backs up plaintext of all iMessages from the device to Apple, with Apple keys (non-e2e). It also includes all SMS. This is documented plainly on Apple's iCloud security overview page. The list of things that are end-to-end encrypted is listed. iCloud Backup is not in it. It's on by default on all iOS devices. Apple was to fix this by end to end encrypting iCloud device backups, and (I understand) even had an implementation, but stopped its deployment on request of the FBI to preserve access to phone contents (including iMessage/SMS history). https://www.reuters.com/article/us-apple-fbi-icloud-exclusive-idUSKBN1ZK1CT https://www.reuters.com/article/us-apple-fbi-icloud-exclusiv...

api 6y ago
So turn off iCloud backups?
- sneak 6y ago
  Then your conversation plaintext gets escrowed to Apple via just Bob instead of both Alice and Bob. (Conversations are backed up twice: once by each party.) You'd need everyone you talk to to also disable iCloud Backup. This is pretty unlikely. Easier to just use Signal, where the chat history isn't included in the device backups at all.
  - saurik 6y ago
    Signal doesn't--and can't--somehow magically prevent people from backing up their messages insecurely. That they don't support being backed up by normal backup methods on iOS--including highly-secure ones--is a missing feature (and a devastating one at that: people expect to have access to their old messages) more than a security measure. Consider this: the existence of a popular tool that helps people back up their Signal messages wouldn't somehow cause it to be accurate to claim there is a "backdoor" in Signal.
    - sneak 6y ago
      If that tool shipped as part of iOS, were on by default, and silently sent the full message history plaintext to Apple (such as if Apple iCloud Backup stopped respecting the storage class of apps and just backed up EVERY FILE), I think it would be fair to call that a backdoor (in iOS). What if iCloud Backup started including in the backup a snapshot of device RAM? I think we are splitting hairs here. The desire of users for message history in backups is entirely orthogonal to whether or not iCloud Backup is a cryptographic backdoor, in the traditional "plaintext escrow" sense. Indeed, the FBI would not have torpedoed Apple's e2e encrypted device backup system if not. Really it boils down to the fact that it's on by default and the users were never asked to consent to their full chat history being transmitted to Apple effectively in the clear. I imagine most users are unaware of the fact that the FBI has warrantless access to every iMessage they have ever sent or received.
      - saurik 6y ago
        Call a spade a spade: if iCloud Backup is insecure (and it is), then say iCloud Backup is insecure, not iMessage. Your stance on this is FUD because you don't respect the semantic boundaries of the systems you are discussing, and so anyone who decides to truly listen to you and internalize the things you say leaves with a broken mental model rather than an educated stance :/. Every single person who reads what you say "iMessage, now backdoored for the FBI" who decides to stop using iMessage (which wasn't even insecure to begin with) and does NOT decide to stop using iCloud Backup (which will be insecure even if the user is using Signal, along with Signal's iOS product flaw that attempts to circular file your messages, as messaging is but one of myriad things a user does on their phone) is someone you have failed by teaching them the wrong lesson.
        sneak 6y ago
        I think that iMessage is simply a feature of iOS, same as iCloud Backup. They can't be installed or used separately, they are a single atom. A single atom with message plaintext escrow enabled by default: a backdoor. By your reasoning, would "iOS is insecure" be an accurate statement?
saurik 6y ago
iCloud Backup being insecure does NOT mean iMessage is "backdoored": if you don't use iCloud Backup--and there is no reason to do so, as Apple (notably unlike anything Android) has a really good local way to do highly-secure backups using iTunes--my (rather firm) understanding is that, even if you turn on the iCloud iMessage sync (which is also optional: I do not have it on, for example), iMessage actually is pretty damned secure (with no key escrow). I appreciate that a lot of people--maybe most or even "almost all" people!--use iCloud Backup, but semantics matter as you present it as if iMessage is insecure, when not only the "real" but the only issue is iCloud Backups (which we should be making sure people don't use, with targeted education campaigns, as it isn't like using Signal could ever solve this issue for all of the other personal data the user had). If you want to make this kind of argument, you need to be doing it from a place of being more informed; like, you could be trying to poke at how the protocol had a weakness--found by pod2g's team--with respect to Apple's ability to inject new keys for existing chat participants, an issue I am not sure they fixed (or even could fix, as it is arguably a UI security problem... but maybe they did, as I don't always follow the blow-by-blow); but this indirect argument you make is FUD.
- fsflover 6y ago
  > iCloud Backup being insecure does NOT mean iMessage is "backdoored" Technically not, but in practice it is for the most users.

fsflover 6y ago

Without the source code, you should provide evidence that it's not backdoored. Given how large Apple is, how big its userbase, I am sure all agencies do everything possible to get the precious data.