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The NCMEC database is large and graded to distinguish types of photos. There’s evidence in the false positive calculations that Apple is only using a subset, pr

The NCMEC database is large and graded to distinguish types of photos. There’s evidence in the false positive calculations that Apple is only using a subset, presumably the one where photos are graded as depicting active abuse. It’s not reasonable to dispute the 1 in 1e12 false positive claim on mere speculation.

brokenmachine 5y ago
>It’s not reasonable to dispute the 1 in 1e12 false positive claim on mere speculation. It's entirely reasonable. Have you seen https://thishashcollisionisnotporn.com/ https://thishashcollisionisnotporn.com/ ? Extraordinary claims require extraordinary evidence.
- simondotau 5y ago
  Collision attacks make for a fun tech demo, but I've yet to hear anyone suggest any plausible scenario where they could be used against Apple's implementation. It would require absurdly elaborate, Oceans Eleven style espionage to achieve any outcome whatsoever. And it would be immediately apparent to anyone involved that a collision attack was involved. It would be far easier (and far more effective) to just acquire child porn, break into your victim's house, stash physical prints under their mattress, and then contact the police. Furthermore, the website includes numerous misleading statements about Apple's system, or makes critical omissions on the description of Apple's system. Whatever side you're on, misleading arguments should be dismissed for what they are.
- shuckles 5y ago
  This is apples to oranges. The whole thread was about random false positives and not adversarial ones.
  - brokenmachine 5y ago
    If it's that easy to generate a false positive then I believe it will be more common to accidentally have one. Onge again, extraordinary claims require extraordinary evidence.
    - simondotau 5y ago
      The ease of adversarial collisions has no relationship to the probability of natural collisions. It's entirely possible to make a cryptographic hash algorithm that has an exceptionally low probability of natural collisions but where adversarial collisions are trivial. It's also possible to create a cryptographic hash algorithm where occasional natural collisions are expected, but adversarial collisions require brute force.

brokenmachine 5y ago

>It’s not reasonable to dispute the 1 in 1e12 false positive claim on mere speculation. It's entirely reasonable. Have you seen https://thishashcollisionisnotporn.com/ https://thishashcollisionisnotporn.com/ ? Extraordinary claims require extraordinary evidence.

simondotau 5y ago
Collision attacks make for a fun tech demo, but I've yet to hear anyone suggest any plausible scenario where they could be used against Apple's implementation. It would require absurdly elaborate, Oceans Eleven style espionage to achieve any outcome whatsoever. And it would be immediately apparent to anyone involved that a collision attack was involved. It would be far easier (and far more effective) to just acquire child porn, break into your victim's house, stash physical prints under their mattress, and then contact the police. Furthermore, the website includes numerous misleading statements about Apple's system, or makes critical omissions on the description of Apple's system. Whatever side you're on, misleading arguments should be dismissed for what they are.
shuckles 5y ago
This is apples to oranges. The whole thread was about random false positives and not adversarial ones.
- brokenmachine 5y ago
  If it's that easy to generate a false positive then I believe it will be more common to accidentally have one. Onge again, extraordinary claims require extraordinary evidence.
  - simondotau 5y ago
    The ease of adversarial collisions has no relationship to the probability of natural collisions. It's entirely possible to make a cryptographic hash algorithm that has an exceptionally low probability of natural collisions but where adversarial collisions are trivial. It's also possible to create a cryptographic hash algorithm where occasional natural collisions are expected, but adversarial collisions require brute force.