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Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

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Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#251

Post by judge2020 »

robertoandred wrote: post #173
judge2020 wrote: post #113

Earlier quoted context omitted.

This has technically been proven false: > Microsoft says that the "PhotoDNA hash is not reversible". That's not true. PhotoDNA hashes can be projected into a 26x26 grayscale image that is only a little blurry. 26x26 is larger than most desktop icons; it's enough detail to recognize people and objects. Reversing a PhotoDNA hash is no more complicated than solving a 26x26 Sudoku puzzle; a task well-suited for computers…

PhotoDNA and NeuralHash are not the same thing.

Apple is using a private perceptual hash on the backend, likely to further filter out bad/spam tickets.

https://twitter.com/fayfiftynine/status/1427899951120490497?...

Given neuralhash is a hash of a hash, I imagine they’re running photodna and not some custom solution which would require Apple ingesting and hasing all of the images themselves using another custom perceptual hash system.

> . Instead of scanning images in the cloud, the system performs on-device matching using a database of known CSAM image hashes provided by NCMEC and other child-safety organizations. Apple further transforms this database into an unreadable set of hashes, which is securely stored on users’ devices.

https://www.apple.com/child-safety/pdf/CSAM_Detection_Techni...

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#252

Post by zepto »

mschuster91 wrote: post #139
helen___keller wrote: post #97

Earlier quoted context omitted.

> I just don't understand how they acted this way at all. There's a simple answer to this right? Despite everyone's reaction, Apple genuinely believe this is a novel and unique method to catch CSAM without invading people's privacy. And if you look at it from Apple's point of view that's correct: other major cloud providers catch CSAM content on their platform by inspecting every file uploaded, i.e. total invasion of…

> Apple found a way to preserve that privacy but still catch the bad people doing very bad things to children. They're not going to find predators, all they are going to find is people incompetent enough to have years old (otherwise how would it end up at NCMEC?) CSAM on their iPhones and dumb enough to have iCloud backup turned on. To catch actual predators they would need to run AI scanning on phones for all photos…

> people incompetent enough to have years old (otherwise how would it end up at NCMEC?) CSAM on their iPhones

Who do you think has 30 or more CSAM images on their phone?

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#253

Post by zepto »

pasquinelli wrote: post #192
GeekyBear wrote: post #175

Earlier quoted context omitted.

ON YOUR DEVICE (where it's encrypted in a way that Apple can't read until the 30 image threshold is crossed) is more private than doing the same scan on server where a single false positive can be misused by anyone who can get a subpoena.

what kind of encryption can't be decrypted until some threshold has been crossed? maybe you mean to say that apple says they won't read it until that threshold has been crossed.

> what kind of encryption can't be decrypted until some threshold has been crossed?

The kind Apple has built. You should read the docs. This is literally how it works.

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#254

Post by rfd4sgmk8u »

Spivak wrote: post #174
orangeoxidation wrote: post #143

Earlier quoted context omitted.

Making it obviously and unquestionably more invasive.

I just don't get this. Say you're given two options when going through the TSA. 1. The TSA agent opens your luggage and searches everything for banned items. 2. The TSA agent hands you a scanner for you to wave over your luggage in private, it prints out a receipt of banned items it saw, and you present that receipt to the agent. Which one is more invasive?

1. Cops on the street 2. Cops in your house

Which one is more invasive?

I don't think there is much to not understand. Apple is proposing putting a cop in your house. On device scanning is vastly vastly different than server side scanning. One is over apples property, the other is over YOUR property. Its a big deal, and a huge change in policy. And as myself and others have indicated from years of observation, it will grow and grow...

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#255

Post by rblatz »

GeekyBear wrote: post #88
epistasis wrote: post #42

What's shocking to me is how little Apple management understood of what their actions looked like. Really stunning. For a company that marketed itself as one of the few digital service providers that consumers could trust, I just don't understand how they acted this way at all. Either there will be heads rolling at management, or Apple takes a permanent hit to consumer trust.

The thing that's shocking to me is that Google, Microsoft and all the big names in tech have been scanning everything in your account (email, cloud drive, photos, etc) for the past decade, without any noticeable uproar. Apple announces that it is going to start scanning iCloud Photos only, and that their system is set to ignore anything below a threshold of ~30 positives before triggering a human review, and people l…

Because it isn’t about the CSAM scanning. Apple keeps reframing the argument back to that. most people expect that google and Microsoft to scan files on their servers for CSAM, people object to Apple turning your phone against its owner, and once building out the capability to do this only policy prevents it from being abused.

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#256

Post by shapefrog »

__blockcipher__ wrote: post #160
shapefrog wrote: post #148

Earlier quoted context omitted.

> B) They scan everything that exists on my device No ... They scan everything that I have released to apple photos that exists on my device. Same scan - different place.

The issue is that as soon as you set that precedent, it’s only a matter of time before it extends beyond iCloud. That’s the problem with doing any device-level scanning. This is dystopian and scary. And yes I understand the technology in its current iteration. The current form has problems (weaponizing collisions etc) but the real issue comes with future developments.

> They scan everything that exists on my device

I get to select the issue and it was in response to the previous claim that 'they' are scanning everything that exists on the device right now.

A year ago this was a possible 'future development'. 10 years from now I could be living on Mars. This is all hypothetical.

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#257

Post by telside »

GeekyBear wrote: post #213
pasquinelli wrote: post #192

Earlier quoted context omitted.

what kind of encryption can't be decrypted until some threshold has been crossed? maybe you mean to say that apple says they won't read it until that threshold has been crossed.

No, I'm saying they designed the system so that they don't have the key to decypt the scan result "vouchers" until after the device tells them that the 30 image threshold is crossed. >Apple is unable to process individual vouchers; instead, all the properties of our system mean that it’s only once an account has accumulated a collection of vouchers associated with illegal, known CSAM images that we are able to learn…

The lady doth protest too much, methinks

Just going to respond to every post on here with these absurd points? K apple guy.

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#258

Post by bsql »

codeecan wrote: post #200
slg wrote: post #149

Earlier quoted context omitted.

Apple controls the hardware, software, and cloud service. It was always a pinky promise that they wouldn't look at your files. I don't know why we should doubt that pinky promise less today than we did a month ago.

They don't control the database used, any country can thru legal means attach additional hashes for search and reporting. Apple has already proven it will concede to China's demands. They are building the worlds most pervasive surveillance system and when the worlds governments come knocking to use it ... they will throw their hands up and feed you the "Apple complies with all local laws etc.."

Do any of the other companies control the database of hashes they use? A government could have already done what you’re suggesting but I can’t find a source where this has been the case.

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#259

Post by mavhc »

_2d30 wrote: post #234
mavhc wrote: post #197

Earlier quoted context omitted.

Why did you think you owned a closed source device?

Open Source fanatics are the worst. Even if all the software on your phone was Open Source, you wouldn’t have the mental bandwidth to ever verify you trust it. You’re just farming out your trust to a different set of people and hoping they’re more trustworthy than those with closed source. At best this MAY be reasonable because of incentive alignment but that’s super weak. Not to mention the meaning of ownership is c…

That's because your fan is hardware and your phone is software. The hardware in your phone is only 1% of what your phone is.

The point is it's hard to hide your evil plans in daylight. Either you trust Apple or your don't. Same with Microsoft's telemetry, they wrote the whole OS, if they were evil they have 10000 easier ways to do it.

All Apple has to do is lie, you'll never know.

Re: Apple defends anti-child abuse imagery tech after claims of ‘hash collisions’

#260

Post by Syonyk »

unyttigfjelltol wrote: post #228
helen___keller wrote: post #97

Earlier quoted context omitted.

> I just don't understand how they acted this way at all. There's a simple answer to this right? Despite everyone's reaction, Apple genuinely believe this is a novel and unique method to catch CSAM without invading people's privacy. And if you look at it from Apple's point of view that's correct: other major cloud providers catch CSAM content on their platform by inspecting every file uploaded, i.e. total invasion of…

Maybe Apple was focused on keeping CSAM off a cloud resource that really is Apple's in both a practical and technical sense. Merely scanning after upload maybe doesn't accomplish that because the material already has arrived in an Apple resource and someone might define that as a failure. Viewed from a perspective of iCloud compliance it sorta makes sense. No one ought to feel a lot of (legal) security deploying a sy…

With the new system, it still arrives on the server, and they can't even know about it until some threshold has been passed - and then the servers still have to scan it.

So it's not even accomplishing "keeping it off the servers."

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