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> reject the unlikely possibility "Unlikely possibility" shows either blatant facetiousness or blatant ignorance. Who couldn't predict the explosion of collisi

> reject the unlikely possibility "Unlikely possibility" shows either blatant facetiousness or blatant ignorance. Who couldn't predict the explosion of collision-generating projects?

nicce 5y ago
You either have to break their HSM (hardware security module), or their cryptography to access for the known hashes. Or get them from elsewhere. Owning the actual images is illegal. It is hard to see the explosion of these projects. You need 30 matching hashes to their database to trigger anything.
- belltaco 5y ago
  >Owning the actual images is illegal Yeah it's not like there are a lot of people on the darknet that do illegal things all the time. /s You only need one of them to compute the neural hashes of the images and then upload them. For others, it is not illegal to have or distribute the neural hashes.
  - nicce 5y ago
    > Yeah it's not like there are a lot of people on the darknet that do illegal things all the time. /s How many of them are developers with enough knowledge compared to all developers in world with enough knowledge? And willing to touch CSAM material? I think there is a quite difference. And they have better things to do than pranking some people. Because you are not getting jailed from hash collisions in the country with working judicial system. You have bigger problems if judicial system is not working.
- zargon 5y ago
  Criminals won't be able to create hash collisions because the images are illegal to possess! Illegal, I say. That is surest way to stop criminals.
  - nicce 5y ago
    Something being very illegal certainly limits it from the masses. I am not saying that it prevents the criminals, but it significantly reduces public projects. And on top of that, even the most of the criminals hate pedophiles, so how many is really willing to access CSAM material?
    - zargon 5y ago
      It only takes one to do it and then distribute the hashes.
      - zepto 5y ago
        As pointed out elsewhere. It doesn’t matter. NeuralHash collisions don’t break the system.
  - nullc 5y ago
    You don't need to have illegal images to create collisions with them. You just need someone with illegal images to publish hashes.
- shrimpx 5y ago
  Thanks. I was under the impression that the hashes were easier to get.
  - kristjansson 5y ago
    It's not just that they're hard to get - it's also that no one has demonstrated a preimage attack. So given just an illegal hash one can't construct an innocent image with that hash. These demonstrations show only that a second image can be transformed to have the same hash as a first, given image. As other comments note, that's not a huge increase in difficulty for an adversary willing to deal in actual CSAM.
    - nicce 5y ago
      > no one has demonstrated a preimage attack. So given just an illegal hash one can't construct an innocent image with that hash. These demonstrations show only that a second image can be transformed to have the same hash as a first, given image. Isn’t this exactly like that? Or am I missunderstanding something. https://twitter.com/ghidraninja/status/1428269674912002048?s=20 https://twitter.com/ghidraninja/status/1428269674912002048?s...
      - kristjansson 5y ago
        No. The author describes their process for generating the image down that very thread[0] Quoting the tweet for those who dislike twitter: > The procedure for this was pretty simple: > - Started with a placeholder image > - Got the hash of it > - Changed text of the image to match the hash > - Then used > @anishathalye great neural-hash-collider which took only 1-2 iterations N.B. it starts with 'started with an image, and the hash of it' [0]: https://twitter.com/ghidraninja/status/1428270675010199554 https://twitter.com/ghidraninja/status/1428270675010199554
        nicce 5y ago
        What is the practical difference? It is forged innocent image which has matching hash. You basically started with only a hash, as image was not related to it.

> reject the unlikely possibility "Unlikely possibility" shows either blatant facetiousness or blatant ignorance. Who couldn't predict the explosion of collision-generating projects?

nicce 5y ago

You either have to break their HSM (hardware security module), or their cryptography to access for the known hashes. Or get them from elsewhere. Owning the actual images is illegal. It is hard to see the explosion of these projects. You need 30 matching hashes to their database to trigger anything.

belltaco 5y ago
>Owning the actual images is illegal Yeah it's not like there are a lot of people on the darknet that do illegal things all the time. /s You only need one of them to compute the neural hashes of the images and then upload them. For others, it is not illegal to have or distribute the neural hashes.
- nicce 5y ago
  > Yeah it's not like there are a lot of people on the darknet that do illegal things all the time. /s How many of them are developers with enough knowledge compared to all developers in world with enough knowledge? And willing to touch CSAM material? I think there is a quite difference. And they have better things to do than pranking some people. Because you are not getting jailed from hash collisions in the country with working judicial system. You have bigger problems if judicial system is not working.
zargon 5y ago
Criminals won't be able to create hash collisions because the images are illegal to possess! Illegal, I say. That is surest way to stop criminals.
- nicce 5y ago
  Something being very illegal certainly limits it from the masses. I am not saying that it prevents the criminals, but it significantly reduces public projects. And on top of that, even the most of the criminals hate pedophiles, so how many is really willing to access CSAM material?
  - zargon 5y ago
    It only takes one to do it and then distribute the hashes.
    - zepto 5y ago
      As pointed out elsewhere. It doesn’t matter. NeuralHash collisions don’t break the system.
- nullc 5y ago
  You don't need to have illegal images to create collisions with them. You just need someone with illegal images to publish hashes.
shrimpx 5y ago
Thanks. I was under the impression that the hashes were easier to get.
- kristjansson 5y ago
  It's not just that they're hard to get - it's also that no one has demonstrated a preimage attack. So given just an illegal hash one can't construct an innocent image with that hash. These demonstrations show only that a second image can be transformed to have the same hash as a first, given image. As other comments note, that's not a huge increase in difficulty for an adversary willing to deal in actual CSAM.
  - nicce 5y ago
    > no one has demonstrated a preimage attack. So given just an illegal hash one can't construct an innocent image with that hash. These demonstrations show only that a second image can be transformed to have the same hash as a first, given image. Isn’t this exactly like that? Or am I missunderstanding something. https://twitter.com/ghidraninja/status/1428269674912002048?s=20 https://twitter.com/ghidraninja/status/1428269674912002048?s...
    - kristjansson 5y ago
      No. The author describes their process for generating the image down that very thread[0] Quoting the tweet for those who dislike twitter: > The procedure for this was pretty simple: > - Started with a placeholder image > - Got the hash of it > - Changed text of the image to match the hash > - Then used > @anishathalye great neural-hash-collider which took only 1-2 iterations N.B. it starts with 'started with an image, and the hash of it' [0]: https://twitter.com/ghidraninja/status/1428270675010199554 https://twitter.com/ghidraninja/status/1428270675010199554
      - nicce 5y ago
        What is the practical difference? It is forged innocent image which has matching hash. You basically started with only a hash, as image was not related to it.