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Apple plans to scan US iPhones for child abuse imagery

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Re: Apple plans to scan US iPhones for child abuse imagery

#251

Post by clusterfish »

colinmhayes wrote: post #131
imroot wrote: post #3

https://towardsdatascience.com/black-box-attacks-on-perceptu... I mean, who's to say that my hash is actually what they think it is... ...and if it's not uploaded to iCloud for someone to manually review what the image is, is that going to be enough to get a search warrant for my phone? "AUSA SOMEONE: But, Your Honor, The Defendant's phone has an image that matched a hash of a CSAM picture!" "DEFENDANT: I'm not going…

Fifth amendment holds that the state can't compel someone to give up their password.

Except 100 miles from the border apparently

https://www.aclu.org/other/constitution-100-mile-border-zone

Re: Apple plans to scan US iPhones for child abuse imagery

#252

Post by wang_li »

jandrese wrote: post #104
partiallypro wrote: post #14

I really don't see how this is going to end well, there could be perfectly innocent photos on someone's phone of their own children doing perfectly normal things that kids do. Like a kid running butt naked around the house, or a photo of something like a rash that is sent to a nurse friend for advice on what it is etc. I'm all for protecting children from being abused, but how are they going to filter what is normal…

Or when an internet troll gets your email address and/or phone number and starts spamming you with child porn pictures, which your phone immediately identifies and notifies authorities.

And to get cleared you’re going to have to let law enforcement clone and inspect the content of your phone.

Re: Apple plans to scan US iPhones for child abuse imagery

#253

Post by diebeforei485 »

fallingknife wrote: post #223
mm983 wrote: post #213

Earlier quoted context omitted.

Again, you don't appear to know how this works. Look up fuzzy hash, i even mentioned it in the comment.

I have a hard time believing that this algorithm will be able to resist simple image manipulations while still being sensitive enough to avoid false positives.

I have similar qualms with this, because this is increasing the number of photos scanned by 2-3 orders of magnitude, and the number of false positives presumably also increases correspondingly.

Re: Apple plans to scan US iPhones for child abuse imagery

#254

Post by elzbardico »

trasz wrote: post #203
marderfarker2 wrote: post #160

Earlier quoted context omitted.

> will initially roll out only in the US. Ok so they’re planning to eventually roll out this spyware worldwide. I do not know how Americans can think China is bad in this while allowing this to happen.

Never ceases to amaze how people believe that China is somehow more oppressive than the the country with world highest incarceration rate.

China have actual slaves. You can't even know the real rate of incarceration in China, and trying to figure it out is almost a sure way to get arrested.

Re: Apple plans to scan US iPhones for child abuse imagery

#255

Post by BitwiseFool »

mm983 wrote: post #212
BitwiseFool wrote: post #193

Earlier quoted context omitted.

>"have the complainers suggest a solution" Being worried about privacy, establishing a precedent for scanning my data against a government database, and the risk of false positives with such an insanely emotionally charged crime is more than mere complaining . The onus should not be on me to justify why this shouldn't be done. This is something new and it is perfectly fine to argue against it without needing to provi…

>That being said, my solution is to continue to follow the process that law enforcement is currently using. If you knew how they approach this you wouldn't be satisfied either

This all boils down to the classic "Liberty vs. Security" dilemma. While I obviously want to see more prosecutions for people who commit these crimes, a value judgement must be made about what it takes to achieve that.

Re: Apple plans to scan US iPhones for child abuse imagery

#256

Post by kevin_thibedeau »

runawaybottle wrote: post #47

It’s 2035, a major terrorist attack occurs. Apple scans all phones for location and images near the area over the last 12 months, sends the list over since the government declared Marshall law. You are now suspicious until proven not suspicious. The real terrorists don’t even use iPhones. But here we are. Edit: Can any legal-heads explain how this does not constitute unlawful search? Apple is not the government, but…

> isn’t the government indirectly committing unlawful search?

No. That's the beauty of the third-party doctrine. Your rights disappear in a puff of twisted logic because you agreed to the fine print.

Re: Apple plans to scan US iPhones for child abuse imagery

#257

Post by heavyset_go »

mlac wrote: post #102
1-6 wrote: post #23

Earlier quoted context omitted.

What will happen is that criminals who actually had bad intent will move off of the platform and the ones who get the brunt of the blame are the innocent who had no ill intent.

The process is described above, but it’s very hard to “innocently” end up with one of those images that they are looking for from the database. And the way it’s being done (hashes), a collision is highly unlikely. If it does occur it doesn’t mean it’s similar in nature (e.g. innocent picture of own child in bath). The hash isn’t looking at the image content in the sense of “what’s in the picture”, just the bits of th…

> The process is described above, but it’s very hard to “innocently” end up with one of those images that they are looking for from the database.

Actually, it's very easy to end up with an image that has a similar perceptual hash to an illegal image.

They are not doing MD5 hashing, they're taking perceptual hashes and then using something like the hamming distance or Levenshtein distance to make a fuzzy match with hashes from illegal images.

I've built products using these methods, and it is incredibly easy to make a fuzzy match based on perceptual hashes from two images that have nothing to do with each other.

Re: Apple plans to scan US iPhones for child abuse imagery

#258

Post by ggreer »

trasz wrote: post #203
marderfarker2 wrote: post #160

Earlier quoted context omitted.

> will initially roll out only in the US. Ok so they’re planning to eventually roll out this spyware worldwide. I do not know how Americans can think China is bad in this while allowing this to happen.

Never ceases to amaze how people believe that China is somehow more oppressive than the the country with world highest incarceration rate.

The US has a high incarceration rate because it has a high crime rate. If EU countries had US levels of crime, they'd have US levels of incarceration.

Also China doesn't count Uyghurs as incarcerated despite the fact that the PRC is committing genocide against them.[1] The PRC imprisons almost 2 million of Uyghurs a year. Of those, around a quarter million die. Oh and there's the forced sterilizations, destruction of mosques, brainwashing, banning of muslim-sounding names[2], forced labor, organ harvesting, and mandatory quartering of government agents.[3]

1. https://en.wikipedia.org/wiki/Uyghur_genocide

2. https://en.wikipedia.org/wiki/Naming_laws_in_China

3. https://en.wikipedia.org/wiki/Civil_Servant-Family_Pair_Up

Re: Apple plans to scan US iPhones for child abuse imagery

#259

Post by rovr138 »

myrandomcomment wrote: post #136
barbazoo wrote: post #56

Earlier quoted context omitted.

> They are using a library of human verified images to compare the hashes I didn't get that from the article, could you point to a source on this?

Directly said in the article: “Users’ photos, converted into a string of numbers through a process known as “hashing”, will be compared with those on a database of known images of child sexual abuse.”

> The system has been trained on 200,000 sex abuse images collected by the US non-profit National Center for Missing and Exploited Children.

Also from the article.

‘Trained’ being important.

Re: Apple plans to scan US iPhones for child abuse imagery

#260

Post by gpm »

maerF0x0 wrote: post #151
__blockcipher__ wrote: post #126

Earlier quoted context omitted.

You have two primary misunderstandings AFAICT. (1) You're assuming it's a "traditional" hash, as opposed to a perceptual hash. The former is purely based off file contents and thus any transformations applied on an image will lead to a new pseudorandom hash. By contrast, perceptual hashes are made to be able to still return a positive when a photo is resized, accumulated artifacts etc. This proposal is to use phashes…

irrc a cryptosecure hash is computationally infeasible to generate a new sample that has the same hash. that is if you know hash (or reasonably small, ie only a percent of the total bit space), it's improbable bordering on impossible to generate a false positive .

Repeating that this process doesn't appear to be using cryptographic hash functions in the first place, so this conversation isn't relevant, but:

Only in the sense that "we don't know of a way to generate a new sample that has the same hash, yet". Unless we can prove P!=NP, we can't even prove that there exist hash functions that are actually infeasible to generate a sample with the same hash - so far we are no where close to knowing whether P!=NP or P=NP.

Even if we assume P!=NP, that doesn't mean that it is infeasible to generate collisions for our current cryptographic hash functions. They're not backed by some mathematical proof of correctness assuming , just the fact that so far no one has publicly figured out a way to break them, and the people who spend time trying think that their design is one that is unlikely to be broken in the near future.

We have managed to find collisions against hash functions that we previously considered cryptographically secure, that were designed with the same sort of standard in mind: E.g. md5 (https://en.wikipedia.org/wiki/MD5#Collision_vulnerabilities) and sha1 (https://en.wikipedia.org/wiki/SHA-1#Birthday-Near-Collision_...).

There's no great reason to think that private groups could not have an attack against current hash functions [1], and there's definitely no reason to think that they won't find one in the future.

[1] There sort of is for SHA2, and that's that bitcoin has effectively created a giant bounty for breaking it.

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