3 ms·

You are still trying to skirt round the point that all stars must align for this attack to work. And there are enough stars to make it an absurd proposition. Mu

You are still trying to skirt round the point that all stars must align for this attack to work. And there are enough stars to make it an absurd proposition. Multiply these likelihoods together and it quickly surpasses the likelihood that the user getting struck by lightning at the exact moment that they win the lottery. As for your images, please. Your new example is substantially worse than your Lenna. Absolutely anyone could see that this image is unusual, even if they couldn't be sure if it was physical or digital damage. I know it's an inappropriate thing to say on HN but claiming that the "image wouldn't strike anyone as unusual" is so far beyond reasonable that I feel myself seriously questioning your sincerity.

nullc 5y ago
> all stars must align for this attack to work. I thought I addressed that pretty directly. "Attackers aren't random processes." -- but OK, feel free to be not convinced. > As for your images, please. Your new example is substantially worse than your Lenna. Absolutely anyone could see that this image is unusual, even if they couldn't be sure if it was physical or digital damage. I think it looks like a scan of a crappy smudged 30 year old photograph. Which is also exactly what it is. FWIW, I thought your comment saying the lena was obviously manipulated was transparently in bad faith, but I held my tongue-- so don't feel too guilty. I would take a sizable wager on that people wouldn't identify it as anything special, and I'm quite surprised to hear that you think differently. (In one of the threads I posted in it one of the people through it was the barbara image that was changed rather than the lena one...)
- simondotau 5y ago
  > I thought I addressed that pretty directly. "Attackers aren't random processes." -- but OK, feel free to be not convinced. I'm not convinced that you're being serious. I rejected that response because it's self-evidently absurd. There were twelve mandatory prerequisites I identified for successful exploitation and the vast majority of them are not under the influence of any attacker, no matter how non-random the hypothetical attacker is. Do you understand what happens when you're forced to multiply probabilities? How does this attacker acquire a functioning copy of this secondary hash algorithm, which for all you know is held at least as securely than Apple holds private keys for stuff like iOS cryptographic signing. How does that attacker change the mind of a person who would never import hard core porn into their phone's photo gallery? Do you know if Apple's human review requires fooling one reviewer or multiple? I personally have no idea but as someone who has implemented a human review system for critical data, placing such consequential decisions in the hands of a single human is a non-starter. For all you know, the 30 images will be looked at by 30 different human reviewers. How does the attacker ensure that ALL of them will overlook the absence of a PRE-PUBESCENT CHILD in the photograph? No sir, I do not think you are not being serious. And that's intended as a compliment, because you're clearly a smart person.

nullc 5y ago

> all stars must align for this attack to work. I thought I addressed that pretty directly. "Attackers aren't random processes." -- but OK, feel free to be not convinced. > As for your images, please. Your new example is substantially worse than your Lenna. Absolutely anyone could see that this image is unusual, even if they couldn't be sure if it was physical or digital damage. I think it looks like a scan of a crappy smudged 30 year old photograph. Which is also exactly what it is. FWIW, I thought your comment saying the lena was obviously manipulated was transparently in bad faith, but I held my tongue-- so don't feel too guilty. I would take a sizable wager on that people wouldn't identify it as anything special, and I'm quite surprised to hear that you think differently. (In one of the threads I posted in it one of the people through it was the barbara image that was changed rather than the lena one...)

simondotau 5y ago
> I thought I addressed that pretty directly. "Attackers aren't random processes." -- but OK, feel free to be not convinced. I'm not convinced that you're being serious. I rejected that response because it's self-evidently absurd. There were twelve mandatory prerequisites I identified for successful exploitation and the vast majority of them are not under the influence of any attacker, no matter how non-random the hypothetical attacker is. Do you understand what happens when you're forced to multiply probabilities? How does this attacker acquire a functioning copy of this secondary hash algorithm, which for all you know is held at least as securely than Apple holds private keys for stuff like iOS cryptographic signing. How does that attacker change the mind of a person who would never import hard core porn into their phone's photo gallery? Do you know if Apple's human review requires fooling one reviewer or multiple? I personally have no idea but as someone who has implemented a human review system for critical data, placing such consequential decisions in the hands of a single human is a non-starter. For all you know, the 30 images will be looked at by 30 different human reviewers. How does the attacker ensure that ALL of them will overlook the absence of a PRE-PUBESCENT CHILD in the photograph? No sir, I do not think you are not being serious. And that's intended as a compliment, because you're clearly a smart person.