4 ms·

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.