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Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

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Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#81

Post by tenuousemphasis »

EGreg wrote: post #15
nkingsy wrote: post #3

Step 1: Use Captcha to get free AI training data. Step 2: Sell improved AI. Step 3: Add edge cases to the Captcha that your AI can't handle yet. Go to step 1.

Can someone please explain to me why smart people keep saying that we’ll just build software to detect deepfakes? When AlphaZero plays against itself it just gets better. Once that spread is so narrow, every deviation is in the range of possible error. And it can’t explain WHY a certain move is better or why the picture is a squirrel. And sometimes it can be wrong, but only on hilarious edge cases, in the rest we jus…

I wonder how much more difficult it would be to deepfake a lightfield compared to a regular video.

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#82

Post by asah »

NoNotTheDuo wrote: post #55
Freak_NL wrote: post #33

Earlier quoted context omitted.

Sci-fi author John Varley covered this in one of his novels. In a society where anything digital can be manipulated, the veracity of a speech or event depends on a network of trust and people who witnessed the event in real life . If someone made a speech in front of hundreds of live, physically present spectators, these spectators can then verify the authenticity of any recording, and as long as there people in that…

What happens when there's a global pandemic and everyone is forced to stay home and not attend witness any of these speeches, but instead has to watch the broadcast over the internet and/or TV?

Cool idea for a sci-fi story.

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#83

Post by chrismorgan »

gnopgnip wrote: post #68
comboy wrote: post #65

Earlier quoted context omitted.

If I were Google, I would let it pass (at least where it's not in my own services, not in crucial places), and use that obviously simple heuristic for machine learning so that distinction between human and robot can be taught using many other available variables. Well, I wouldn't really do that if I were Google. But I think it could be happening.

Google doesn't pass or fail, it gives a score and leaves it up to the site operator.

You’re dealing with two different things.

reCAPTCHA v2 and the badly named Invisible reCAPTCHA¹ assess the user and either let them in, or gate them on puzzle solving. So, it does pass or fail you, where fail means trap you in purgatory indefinitely (though some hold it’s actually hell rather than purgatory).

reCAPTCHA v3 never presents a CAPTCHA for you to solve, but decides a score (in practice, I’ve only seen 0.1, 0.3, 0.7 and 0.9) where higher means it’s feeling more friendly towards you, and it’s up to the site operator to decide what to do with it. (You should provide alternative means, e.g. if you’re doing fraud prevention for signup, fall back to SMS verification. Too many sites provide no recourse for a low score, which is illegal to do in various countries on accessibility grounds. With reCAPTCHA v2 and Invisible reCAPTCHA the site owners can at least blame Google, not that that gets them off the hook.)

Given the use of Rekognition here, I presume this project is breaking reCAPTCHA v2 and possibly Invisible reCAPTCHA, and not reCAPTCHA v3.

———

¹ I call Invisible reCAPTCHA badly named because it’s only invisible on the happy path—all it’s doing is hiding the “I’m not a robot” widget, effectively having the code “click” it when submitting. And given that reCAPTCHA v3 is then invisible, never showing anything to the user… yeah, it’s confusing. Arguably reCAPTCHA v3 isn’t even a CAPTCHA any more either, so… yeah, the names are all a bit of a mess.

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#84

Post by notatoad »

gnopgnip wrote: post #68
comboy wrote: post #65

Earlier quoted context omitted.

If I were Google, I would let it pass (at least where it's not in my own services, not in crucial places), and use that obviously simple heuristic for machine learning so that distinction between human and robot can be taught using many other available variables. Well, I wouldn't really do that if I were Google. But I think it could be happening.

Google doesn't pass or fail, it gives a score and leaves it up to the site operator.

they suggest a default 0.5 threshold in their documentation. if you're testing "passing" their captcha, it'd be pretty reasonable to consider anything below that a fail.

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#85

Post by uHuge »

freeone3000 wrote: post #49
crystaln wrote: post #40

Earlier quoted context omitted.

This doesn't work that well in practice: - Humans can lie - Human memory is too fallible to serve as this verification, particularly for every detail - Small details with big impact can be changed in a verified speech without some people noticing Of course if someone reliable records the actual speech, any copy can be checked against that. I'm not sure why human memory would be considered superior, as humans have poo…

How can you tell a true copy from a false copy? What makes one recording more true than the other, if you can only compare it against a reality which no longer exists (because it's in the past)?

I have a simple manufacturing tweak patent for the recorder devices on my table to do so.

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#86

Post by jungletime »

EGreg wrote: post #15
nkingsy wrote: post #3

Step 1: Use Captcha to get free AI training data. Step 2: Sell improved AI. Step 3: Add edge cases to the Captcha that your AI can't handle yet. Go to step 1.

Can someone please explain to me why smart people keep saying that we’ll just build software to detect deepfakes? When AlphaZero plays against itself it just gets better. Once that spread is so narrow, every deviation is in the range of possible error. And it can’t explain WHY a certain move is better or why the picture is a squirrel. And sometimes it can be wrong, but only on hilarious edge cases, in the rest we jus…

I'm not sure if we are there already. The Biden speech at the convention was very good, but the video was immediately claimed to be suspicious. The image had unusual softness around his mouth, compared to rest of the image. The speech was pre-recorded. So post processing could be responsible. But also deepfakes at this point are possible too. So who knows.

https://www.vice.com/en_us/article/7kzj8y/why-joe-bidens-vir...

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#87

Post by notatoad »

chrismorgan wrote: post #83
gnopgnip wrote: post #68

Earlier quoted context omitted.

Google doesn't pass or fail, it gives a score and leaves it up to the site operator.

You’re dealing with two different things. reCAPTCHA v2 and the badly named Invisible reCAPTCHA¹ assess the user and either let them in, or gate them on puzzle solving. So, it does pass or fail you, where fail means trap you in purgatory indefinitely (though some hold it’s actually hell rather than purgatory). reCAPTCHA v3 never presents a CAPTCHA for you to solve, but decides a score (in practice, I’ve only seen 0.1,…

your comment is reasonable, using rekognition for recaptcha v3 wouldn't seem to make sense.

but the linked source code is pretty clearly interpreting scores and referencing recaptcha v3, so i'm not sure what images they're running rekognition on. (unless there's a bunch of stuff going on in this repo and this file is unrelated to the title)

https://bitbucket.org/Pirates-of-Silicon-Hills/voightkampff/...

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#88

Post by uHuge »

qroshan wrote: post #48
3pt14159 wrote: post #35

Earlier quoted context omitted.

What's needed is more cryptography. Build keys into sensors to sign media and use something like blockchain to broadcast the signature at time of capture / time when the device returns to the internet. Won't be perfect, but it would be a hurdle. Also, for things like audio and video if you know the location on the planet then there are certain artifacts that are hard to fake with mere AI. The way sound bounces off wa…

The problem with that is, the video can only be watched at it's true raw form. Any edits will need to be re-signed with "Edited by X". Now, X has to be trusted and not compromised (by money, bias or hacks). If X is CNN, then half the population will not believe it. If X is Fox, the other half won't believe. Bottomline, the world will be truly living in virtual alternative universes and it doesn't even matter what tru…

Watching and verifying are two separate procedures, if the edited piece has a link to the original source, the verification can pass to that.

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#89

Post by EGreg »

h-jones wrote: post #74
jakear wrote: post #50

Earlier quoted context omitted.

Anyone else find it mildly(/extremely) distressing that a large part of our industry is dedicated to creating technology that provides little-to-no value to society, but creates enormous opportunities for great societal damage? We then release the tech to the wild without any proposed way to address the problems, instead saying “the problems this causes are outside the domain of CS, so I won’t bother considering them…

I hope I didn't make it seem like I was pushing the solution onto others when I said that it will move outside the domain of computer science. My research is in the area of detecting deep fakes. You're definitely right about how little we attend to the consequences of our advancements, especially in the field of AI/ML. This area is fraught with ethical and moral issues that have taken a backseat to the ideal of progr…

If there were B and C that would mitigate the bad things in more powerful A, then fine

But otherwise delaying progress what if in the end a more powerful A will eventually make any B and C irrelevant? All you’re doing is kicking the can down the road maybe?

Re: Beating Google ReCaptcha and the funCaptcha using AWS Rekognition

#90

Post by uHuge »

RulerOf wrote: post #80
clairity wrote: post #14

while neat, it's a boon to spammers and other nefarious actors who can use these techniques to further get around captcha... concerning to say the least. if we want to defeat time-wasting and privacy-invading captcha and the murky ethics aren't a concern, then we should go to every e-commerce site that employs them, with full crap-blocking privacy mode on, load up on products/services, and then abandon our carts at t…

>abandon our carts at the captcha. I thought the credit card number was the answer to the captcha on an e-commerce site.

On some yes, but many offer other payment methods.
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