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# AI Solves CAPTCHAs With 66pct Accuracy

#### engine

12:01 pm on Oct 27, 2017 (gmt 0)

joined:May 9, 2000
posts:25663

A new AI is resolving CAPTCHAs with 66% accuracy, compared to a human that is around 87%, mainly because if the interpretations of the image. Typically, if it can be resolved in 1% of the time is a broken CAPTCHA.

Clearly, new AI technology has become too strong to make CAPTCHAs provide any security of evidence of a human interaction. Personally, I always have trouble with the blurred words.
[motherboard.vice.com...]

#### NickMNS

1:23 pm on Oct 27, 2017 (gmt 0)

#### Senior Member

joined:Apr 1, 2016
posts:2233

Great Journalism on the part of Vice [insert sarcasm].

The article amounts to a statement equivalent to "I can pick a lock 66% of the time" There is no mention of what type of lock or how long it took pick it. At the end of the article is does mention the unCaptcha algo that claims to be able to defeat reCaptcha. When you dig deeper into the link provided you see that it can defeat it 81% of the time in 5.4 seconds using the audio.

We have evaluated unCaptcha using over 450 reCaptcha challenges from live websites, and showed that it can solve them with 85.15% accuracy in 5.42 seconds, on average: less time than it takes to even play the audio challenge!

So now lets review:
85.15% accuracy
5.42 seconds + less time than it takes to even play the audio challenge! (note the exclamation point...) so total time say 11 seconds.

24 * 60 * 60 (second in a day) / 11 * 0.81 ~= 63000 attempts.

A 6 letter password (no special characters or numbers) has 1 / 300 M probability. (26**6)

So at a rate of 66000 attempts a day it would take in the order of 4800 days to crack the password on average.

And one more point, there is no mention about resources needed. How much computing power and electricity is this going to cost an attacker.

In conclusion I think Captchas are not yet obsolete.

#### martinibuster

1:36 pm on Oct 27, 2017 (gmt 0)

#### Moderator from US

joined:Apr 13, 2002
posts:14828

That bot is at least as successful as I am in solving those captchas.

:P