back to article Talk about a GAN-do attitude... AI software bots can see through your text CAPTCHAs

If you're one of those people who hates picking out cars, street signs and other objects in CAPTCHA image grids, then get used to it because the days of text-based alternatives are numbered. CAPTCHA stands for "Completely Automated Public Turing test to tell Computers and Humans Apart." CAPTCHA tests are used to separate bots …

  1. Oh Matron!

    GAN see through

    Shame how AI can't teach you how to proof read, though!

    1. Borg.King

      Re: GAN see through

      GAN is an acronym for Generative Adversarial Network.

    2. Michael Wojcik Silver badge

      Re: GAN see through

      You need to update your model to recognize puns.

  2. Shadow Systems

    CAPTCHAs can FOAD.

    Tests designed to weed the Humans from the computers are often difficult if not impossible for the Humans to solve, yet obscenely easy for the Computers to thwart.

    Audio tests that can't be heard by anyone without (perfect) hearing, yet a Computer can filter out the background hiss/cracks/pops/crap to get the code to be repeated.

    Visual tests that can't be properly (or at all) seen by anyone without (perfect) vision, yet the Computers can pick out the bits they need in less time than it takes a Human to even focus on the image in the first place.

    And when the Human fails to get the answer right the first time in the few seconds allowed, we're given a new test to try again... and again... and again... all while the Computer snorted in amusement, handed over the answer, & got past the tester's desk without even breaking stride.

    This is the exact opposite of what the test is supposed to do, yet it's the Humans that get the shaft for our all-too-Human failures.

    Thank you for those CAPTCHAs. I hope you choke on them & die.

    1. Anonymous Coward
      Anonymous Coward

      Re: CAPTCHAs can FOAD.

      I manage a Google Groups and whenever I had to invite a new member I (admin, logged in) have to solve several captchas in sequence (sometimes more than 6 times in a row) for reasons that baffle me. I've already asked for a colleague to set up a proper mailing list that I can manage without identifying enough bicycles for the whole population of China.

      1. Dr Paul Taylor

        American imperialism

        To add to all the other stupidity of Google CAPTCHAs, we have to recognise AMERICAN cars,

        AMERICAN street signs, AMERICAN shop fronts, etc.

        1. ivan5

          Re: American imperialism

          Add to that the fact Google CAPTCHAs don't work on older browsers so sites that use them always get forgotten as I find the information somewhere else.

        2. tiggity Silver badge

          Re: American imperialism

          You beat me to the comment!

          Cultural imperialism at its best - plus people unfamiliar with US signage may easily get things wrong - e.g. tiny low quality images on phone - hard to tell if a fragment of a street sign or a bit of something else.

          Int being a US person and never driven there, no clue on look and feel of US street signage so useless unless it is an obvious sign (and no I'm not going to research US signage just to pass captchas easily).

          Other cultural assumptions I have faced in past captchas include ID the taxi (expecting you to pick yellow cars, and not e.g. black cabs)

          1. GnuTzu

            Re: American imperialism

            Fair enough. It's not as if they can't tell what country you're coming from. It's not as if computing standards have only recently been addressing internationalization. Seriously, this is easily fixable, so what's Google's problem? Why the hell are they taking so long to fix this? Oh right; too big for their britches.

        3. Anonymous Coward
          Anonymous Coward

          Re: American imperialism

          Seriously? Cars look radically different in the UK? Funny, I thought they mostly had four wheels underneath, a painted body shell over all, and a cabin sticking up with windows for the drivers to see out of. Oh hey, that's the same as cars in any country in the world.

          Looking at street view pix of UK storefronts, they look pretty much the same as well. Flat front of a building, one section has a sign of some sort, there's a doorway and probably some glass windows.

          Street signs? Gosh, a vividly-colored metal shape on a pole, set beside the road and facing oncoming traffic. I had no problem recognizing street signs in France and Malaysia, even when I couldn't read them.

          I guess you Brits don't drive in other countries much. You can't find your rental car (strange looking yanno), can't tell what's a street sign, and won't be able to recognize the store you wanted anyway.

          But hey, don't pass up a chance to imply IMPERIALISM over something so silly. As if British companies wouldn't use British imagery!

        4. Michael Wojcik Silver badge

          Re: American imperialism

          we have to recognise AMERICAN cars

          Pfft. How hard can that be? They're just like regular cars, except worse.

      2. whitepines
        Thumb Down

        Re: CAPTCHAs can FOAD.

        I'm sick and tired of providing free machine learning to Google in addition to already having Google slurp as much as they possibly can. It's reached a point where I won't do business with people that require a Google captcha and I hope some kind of legislative solution can be found to the exploitation of free human labor for AI training.

        1. Random Q Hacker

          Re: CAPTCHAs can FOAD.

          My thoughts exactly, why am I providing free labor to google? Especially where a website makes me go through the ordeal more than once. Did I turn from human to robot in the last 30 minutes? Perhaps the AI apocalypse is closer than we think!

    2. brotherelf

      Re: CAPTCHAs can FOAD.

      I have a home-brew captcha on a not very important page that asks you to solve a fairly simple subset-sum problem and rejects you if the answer comes too quickly.

      Come to think of it, for most of our purposes (not a commercially interesting target), I could probably just require that the form submission is more than 5 seconds after the page request, with no security feature at all.

    3. Sir Runcible Spoon

      Re: CAPTCHAs can FOAD.

      I tried to track an item on the Royal Mail website yesterday, it took over 30 attempts for me to get the right combination.

      I mean, is that dot in the distance, mostly obscured by a bush, a car, a lorry or a cyclist?

      Is that a storefront? All I see are Chinese characters on a sign, it could be an old people's home for all I know.

      FOAD indeed. Fucking parcel was here two minutes after I got through it.

    4. Michael Wojcik Silver badge

      Re: CAPTCHAs can FOAD.

      Tests designed to weed the Humans from the computers are often difficult if not impossible for the Humans to solve, yet obscenely easy for the Computers to thwart.

      They're also solving the wrong problem, since even a perfect human-detection test would still stuff from human-based attacks, such as Mechanical-Turk-style paid attackers, and other incentives. I've seen reports of spammers reflecting CAPTCHAs to porn sites, so consumers of the latter solve the CAPTCHA in exchange for product. That sort of thing is trivial to engineer and costs the attackers almost nothing.

      What's needed is a test to see whether the user is both sincere and aware of what resource the test is unlocking. Good luck with that.

    5. Michael Wojcik Silver badge

      Re: CAPTCHAs can FOAD.

      Image and audio CAPTCHAs also have usability issues, and require enabling those media types.

      Also, of course, sometimes there are perfectly valid reasons for automating resource access.

  3. Anonymous Coward
    Anonymous Coward


    " CAPTCHA tests are used to separate bots from people, as many internet users have seen."

    No, CAPTCHA is used to fingerprint users browsers and thus fingerprint the computer and user depending on how uniquie the browsers fingerprint and whatever aggregated data is combined.

    You have to allow cookies, javascript and iframes just for starters before CAPTCHA will even begin to work.

    CAPTCHA is also favorite tool of scumbags that hijack sites to redirect mobile browsers.

  4. DropBear

    While I am indeed one of those people who hates picking out cars, street signs and other objects in CAPTCHA image grids working for Google for free, the part I really hate with impossible-to-properly-describe fury is that apparently there is no limit on how many times you can be forced to try again. Usually it just goes on endlessly, tile set after tile set after tile set, and there is no recourse because a) you probably have something you _need_ to do behind that captcha you can't do anywhere else and b) absolutely everyone is using the same disgusting system anyway.

    The fact that if as a consumer I had any power whatsoever then right now there would be a giant smouldering crater full of liquefied rock where the captcha servers used to be illustrates nicely that I am nothing more than powerless cattle and a product both for the suppliers of those captchas and the sites employing them.

  5. Robert Carnegie Silver badge

    Last time I tried to look up a quantity of addresses in Scotland - at

    After the first few, I got one of those graphical CAPTCHAs. Then a little later, two. Then, four, then eight... then I took a long break.

    (This is for address data that I already have - to check it.)

    This was inconvenient but I respect the goal of preventing data from being ripped wholesale. And I suspect that the results don't need to be 100% correct, and that I'm scored against other human players, not against a computer recognizer... or there would be no point.

    I do think that the pictures are faked anyway because surely American streets don't have that many signs all over them... even in famous small towns which have peculiar traffic regulations specifically to earn fines from unsuspecting visitors.

    1. Michael Wojcik Silver badge

      surely American streets don't have that many signs all over them

      What's "that many"? I've seen plenty of signposts with half a dozen or more signs hung on it. You can find plenty of genuine examples in Google Images, if you're willing to browse for a while.

      Here are a couple of examples from Boston.

      1. Jamie Jones Silver badge
  6. Andy Mac

    I hut a picture-based CAPTCHA today. It asked me to identify cross-walks. Now, not being of the North American persuasion, I couldn’t define what a crosswalk was *exactly*. Was it a zebra crossing, or anything woth traffic lights in it? Whatever I did, it was wrong.

    1. Michael Wojcik Silver badge

      "Crosswalk" ought to refer to the pilgrimage of the Penitentes to Santuario de Chimayo, but sadly does not. In the US, a "crosswalk" is a section of a roadway marked for pedestrian crossing, so more or less what's called a "zebra crossing" in the UK.

      In the US, a "zebra crossing" is a section of roadway where zebras are likely to attempt to cross. They're similar to, but less common than, deer crossings.

  7. Gerry 3

    My whinge about CAPTCHA is that the relevant objects are often not neatly contained within the boxes.

    If it's traffic signs do you just click the main two boxes, or do you include the pole and the 'spillover' boxes ?

    But at least it doesn't ask you to click on the pavement, a stroller or a solicitor...

  8. Anonymous Coward
    Anonymous Coward

    google 1 ; humans 0

    Not much talk about the Google CAPTCHA's actually using humans to create perfect training datasets to teach AI's.

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