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What kind of non-child-porn imagery is so similar to child porn that it fools the NCMEC investigator who is looking at it side-by-side with its maliciously-coll

What kind of non-child-porn imagery is so similar to child porn that it fools the NCMEC investigator who is looking at it side-by-side with its maliciously-collisioned hash match, but is at the same time so so dissimilar from real child porn that, as you say, the target won't report its sudden appearance on their device and the the sender won't be at legal risk? Your scenario requires the image (not the hash, but the regular human-perceptible image) to be both unremarkably innocent and incontrovertibly damning at the same time.

nullc 5y ago
You're assuming that there is a side-by-side comparison with a hash matching image. I think that is an extremely big assumption which assumes facts not in evidence at all. As far as what kind of image would be believed to be child porn without a side-by-side with the supposed match: ordinary porn. Without context plenty would be hard to distinguish, especially with the popularity of waxed smooth bodies and explicit close up shots. Prosecution over "child porn" that isn't is already a proved thing, with instances where the government was happily trotting out 'experts' to claim that the images were clearly a child based on physical characteristics only to be rebuffed by the actual actress taking the stand. ( https://www.crimeandfederalism.com/page/61/ https://www.crimeandfederalism.com/page/61/ )
- hannasanarion 5y ago
  You still haven't explained how an image can be at the same time so benign that the user doesn't delete it from their phone and cloud service and the sender is in no legal danger, and yet so obviously pornographic that a jury will be convinced beyond any reasonable doubt that it's child porn. The entire point of this process is to catch only images from a known catalogue of existing images, of course there will be opportunity for side-by-side comparison. And if the side-by-side comparison can convince a jury that the images are the same, then the result is literally identical to if you had just sent the original image, the hash checking service hasn't impacted the attack whatsoever. The idea that new images of nudity could be caught in it is because of a mixup by the press after it was announced, because people confused it with a different parental control feature that detects nudity in images taken by your kids' phones. This is not the same thing.
  - nullc 5y ago
    I think I explained it adequately. An attacker gets some hashes likely to be in the database. The attacker modified legal pornography of young looking people, perhaps closeups of genitalia, to match the child porn hashes. There are plenty of examples of US persons being charged for lawful pornography which a prosecutor accused of being child porn, I linked to one such example-- where the accused was rescued only by the testimony of the actress, and where the prosecution had expert witnessess testifying that the images of an adult were images of a child. The attacker in this case would know the origin of the images and could point to them. The victim would have no idea where they came from. I have searched the case law, and can find no case where the NCMEC provided an image for comparison. Are you aware of any? You also seem to have continued to move the goalpost. Being merely accused of possessing child porn would be extremely damaging to a person. The fact that they might escape conviction by a jury after years of legal ordeal, incarceration, and having their reputation ruined, is not that much consolation. > The idea that new images of nudity could be caught in it is because This is an absurd claim. I have demonstrated (https://github.com/AsuharietYgvar/AppleNeuralHash2ONNX/issues/1#issuecomment-902977931 https://github.com/AsuharietYgvar/AppleNeuralHash2ONNX/issue...) that it is possible to alter existing images to match an arbitrary neuralhash resulting in a perfectly normal looking image. This point is not a matter for dispute, anymore. I could easily do so with a nude or pornographic image, I only chose to use SFW pictures out of good taste. My interest in apple's scheme arouse out of their malicious use of cryptography to shield their actions from accountability. I didn't even hear about the imessage nudie scanner until some time after. You can be certain no such confusion applies here.

nullc 5y ago

You're assuming that there is a side-by-side comparison with a hash matching image. I think that is an extremely big assumption which assumes facts not in evidence at all. As far as what kind of image would be believed to be child porn without a side-by-side with the supposed match: ordinary porn. Without context plenty would be hard to distinguish, especially with the popularity of waxed smooth bodies and explicit close up shots. Prosecution over "child porn" that isn't is already a proved thing, with instances where the government was happily trotting out 'experts' to claim that the images were clearly a child based on physical characteristics only to be rebuffed by the actual actress taking the stand. ( https://www.crimeandfederalism.com/page/61/ https://www.crimeandfederalism.com/page/61/ )

hannasanarion 5y ago
You still haven't explained how an image can be at the same time so benign that the user doesn't delete it from their phone and cloud service and the sender is in no legal danger, and yet so obviously pornographic that a jury will be convinced beyond any reasonable doubt that it's child porn. The entire point of this process is to catch only images from a known catalogue of existing images, of course there will be opportunity for side-by-side comparison. And if the side-by-side comparison can convince a jury that the images are the same, then the result is literally identical to if you had just sent the original image, the hash checking service hasn't impacted the attack whatsoever. The idea that new images of nudity could be caught in it is because of a mixup by the press after it was announced, because people confused it with a different parental control feature that detects nudity in images taken by your kids' phones. This is not the same thing.
- nullc 5y ago
  I think I explained it adequately. An attacker gets some hashes likely to be in the database. The attacker modified legal pornography of young looking people, perhaps closeups of genitalia, to match the child porn hashes. There are plenty of examples of US persons being charged for lawful pornography which a prosecutor accused of being child porn, I linked to one such example-- where the accused was rescued only by the testimony of the actress, and where the prosecution had expert witnessess testifying that the images of an adult were images of a child. The attacker in this case would know the origin of the images and could point to them. The victim would have no idea where they came from. I have searched the case law, and can find no case where the NCMEC provided an image for comparison. Are you aware of any? You also seem to have continued to move the goalpost. Being merely accused of possessing child porn would be extremely damaging to a person. The fact that they might escape conviction by a jury after years of legal ordeal, incarceration, and having their reputation ruined, is not that much consolation. > The idea that new images of nudity could be caught in it is because This is an absurd claim. I have demonstrated (https://github.com/AsuharietYgvar/AppleNeuralHash2ONNX/issues/1#issuecomment-902977931 https://github.com/AsuharietYgvar/AppleNeuralHash2ONNX/issue...) that it is possible to alter existing images to match an arbitrary neuralhash resulting in a perfectly normal looking image. This point is not a matter for dispute, anymore. I could easily do so with a nude or pornographic image, I only chose to use SFW pictures out of good taste. My interest in apple's scheme arouse out of their malicious use of cryptography to shield their actions from accountability. I didn't even hear about the imessage nudie scanner until some time after. You can be certain no such confusion applies here.