How does the “I’m not a robot” checkbox work? – Medium
Asking you to click a checkbox to confirm that you are, in fact, human seems curiously today’s age, there’s a high chance that you, dear reader, are a machine. Maliciously-programmed internet bots (software applications that can run automated tasks) are an unfortunate commonplace on the internet. They can be used at various scales from generating fake social media accounts, to rapidly booking out all tickets for a popular concert and orchestrating a large-scale Distributed Denial of Service (DDoS) attack; a DDoS is an attempt to make an online service unavailable by overwhelming it with traffic. It’s the type of high-profile attack that can take down everything from banks to government websites. A dystopian world like this needs a reliable way to differentiate an evil bot from a well-intentioned human. How can a banking website be sure that an innocent grandma who is logging in to check that the holiday gift money was successfully transferred to her grandchildren, is in fact, an innocent grandma? Enter, the “Completely Automated Public Turing test to tell Computers and Humans Apart”, or more simply, the like internet bots themselves, and like much of the innovation on the internet, CAPTCHAs find their origin in the hacker community. Back in the ancient 1980s the hackers invented leetspeek to bypass security filtering on internet chat forums. Leet is a method of converting words to lookalike characters or abbreviations that cannot easily be interpreted by a computer:leet > I33tcensored > c3n50redporn (pornography) > pr0nIn the pre-Google days of the internet, websites would be manually submitted to search engines. In order to prevent the submission of fake websites, AltaVista implemented the first CAPTCHA-like system that required a user to type a series of distorted characters into a box. This approach, which we often still encounter when registering new accounts or submitting information on the internet, is based on three principles:Humans can more easily recognise highly distorted, rotated or skewed can more easily visually separate overlapped can more easily draw on context to understand visually distorted characters, for example, identifying a character based on the full word that it appears search engine Alta Vista was one of the first popular websites that introduced a CAPTCHA-like protection when submitting new websites to its 2003, a research team from Carnegie Mellon University published a pioneering research paper that described many different types of software programs that could distinguish humans from computers. It was this group that also coined the catchy acronym. As CAPTCHAs became a status quo of security on the Internet, Luis von Ahn, a member of the original research team, became increasingly uncomfortable with how much valuable time was being wasted on solving these mini puzzles. In a wonderful 2011 TED Talk, von Ahn estimated that humanity as a whole was wasting 500, 000 hours a day on completing Von Ahn discusses how the collective amount of time wasted on filling out CAPTCHAs inspired the reCAPTCHA ioning whether this time could be put to more powerful and meaningful use, he developed reCAPTCHA, which was eventually sold to Google in 2009. These days, there are a number of projects and companies (including Google Books, the Internet Archive, Amazon Kindle and The New York Times) that are scanning and indexing large numbers of books, documents and images for use on the web. reCAPTCHA works by taking any of the scanned words that cannot be recognised and presenting them to a human alongside a known word for interpretation. By typing the known word correctly, you identify yourself as a human and the reCAPTCHA system gains some confidence that you have correctly digitised the second. If 10 other people agree on the transcription of the unknown word, the system will assume this to be correct. Today reCAPTCHA helps to digitise millions of books a year and has also extended to support other efforts like digitising street names and numbers on Google Maps or recognising common objects in photos for Google original reCAPTCHA asks you to type a known scanned word to identify yourself as a human and to help transcribe another word that a computer was not able to forms of CAPTCHAs are also being used to help index images and data captured by Google Street are many other forms of CAPTCHAs, including an audio version for the visually impaired. But it is the curiously simple variety — the “I’m not a robot” checkbox seen on many of today’s websites — that inspired the original question behind this article. This checkbox, endearingly called the “no CAPTCHA reCAPTCHA”, is a Google product that unsurprisingly uses a combination of advanced Google technology to produce a very simple result. Google will analyse your behaviour before, during and after clicking the checkbox to determine whether you appear human. This analysis might include everything from your browsing history (malicious bots don’t necessarily watch a few YouTube videos and check their Gmail before signing up for a bank account), to the way you organically move your mouse on the page. If Google is still unsure of your humanness after clicking the checkbox, you will be shown a visual reCAPTCHA (with words, street signs or images) as an additional security measure. This multi-faceted approach is necessary as computers become more skilled at complex image recognition and with the rise of CAPTCHA sweatshopping (think a large room of underpaid workers tasked with generating a heap of fake social media accounts).
Google Can Now Tell You’re Not a Robot With Just One Click
When Alan Turing first conceived of the Turing Test in 1947, he suggested that a computer program’s resemblance to a human mind could be gauged by making it answer a series of questions written by an interrogator in another room. Jump forward about seven decades, and Google says it’s now developed a Turing Test that can spot a bot by requiring it to do something far simpler: Click on a Wednesday, Google announced that many of its “Captchas”—the squiggled text tests designed to weed out automated spambots—will be reduced to nothing more than a single checkbox next to the statement “I’m not a robot. ” No more typing in distorted words or numbers; Google says it can, in many cases, tell the difference between a person or an automated program simply by tracking clues that don’t involve any user interaction. The giveaways that separate man and machine can be as subtle as how he or she (or it) moves a mouse in the moments before that single click. “For most users, this dramatically simplifies the experience, ” says Vinay Shet, the product manager for Google’s Captcha team. “They basically get a free pass. You can solve the catptcha without having to solve it. ”Google’s new captcha, which requires only a click in a ‘s new captcha, which requires only a click in a stead of depending upon the traditional distorted word test, Google’s “reCaptcha” examines cues every user unwittingly provides: IP addresses and cookies provide evidence that the user is the same friendly human Google remembers from elsewhere on the Web. And Shet says even the tiny movements a user’s mouse makes as it hovers and approaches a checkbox can help reveal an automated bot. “All of this gives us a model of how a human behaves, ” says Shet. “It’s a whole bag of cues that make this hard to spoof for a bot. ” He adds that Google also will use other variables that it is keeping secret—revealing them, he says, would help botmasters improve their software and undermine Google’s cases where a mere click doesn’t produce a conclusive response, a pop-up window will require users to decipher the same old distorted text. In tests during the past week on sites that use Google’s captcha, however, it’s verified most human users without that backup. About 60 percent of WordPress users and 80 percent of users at video game sales site Humble Bundle got past the captcha with only the ‘s new captcha for mobile users asks them to complete image recognition tasks that might be hard for ‘s new captcha for mobile users asks them to complete image recognition tasks that might be hard for smartphone and tablet users, Google hasn’t simplified its captcha to a single click. Instead, it will show users a collection of images and ask them to make distinctions that might be tough for bots. For instance, it might display a picture of a cat and ask the user to tap the images that match it among eight photos of other cats, dogs, gerbils and desktop users, however, it’s no surprise that Google can now block bots based on a single click. Google has been working on that same problem for years to stymie “click fraud, ” the nonhuman scourge that clicks on pay-per-click ads to generate revenue for the sites that host them. And Google has also been invisibly integrating automated bot-detection into its captchas since at least 2013. In October of last year it revealed it was using “advanced risk analysis” in captchas to identify automated bad actors. And on Valentine’s Day of this year, it experimented with showing users simple, undistorted words like “Love” and “Flowers, ” and depended on that advanced risk analysis to filter out bots that could easily use image recognition to read those latest evolution may go too far for some; privacy-conscious users won’t appreciate the reminder that Google can learn—or already knows—so much about them based only on simple clues they reveal in their online Google’s Shet points out that when its captchas appear on other sites, Google will only be able to track the user’s movements over the captcha widget, not the whole page. And he argues that captchas are, by their very nature, good for privacy: They provide a way to show you’re a good user, rather than an evil bot, without logging in to a service or coughing up identifying details. “You don’t have to verify your identity, ” Shet says, “to verify your humanity. ”
CAPTCHA: Hard for Humans, Easy for Bots – PerimeterX
CAPTCHA: A Well-worn Approach to Bot Defense
For years, website owners have used a number of approaches and technologies to battle constantly evolving bot threats. One of the most common ways to battle bots has been to use CAPTCHAs, a challenge-response mechanism that promised an easy way to distinguish between a bot and a human. CAPTCHA is an acronym for completely automated public Turing test to tell computers and humans apart. Used in millions of sites, CAPTCHA is employed to help prevent bots from doing form submissions, executing logins and accessing sensitive pages or processes.
How CAPTCHA Has Evolved
As bot-based threats have evolved, so have the CAPTCHA mechanisms intended to stop them. In its early forms, users were asked to read distorted text and submit it in a form.
An example of one of the types of Google reCAPTCHAs that are most commonly used today.
Today, Google reCAPTCHA represents the dominant form of CAPTCHA technology in use. One study found that, across one million of the world’s top websites that employ CAPTCHA, Google reCAPTCHA was deployed by 94% of them.
How CAPTCHA Is Failing
In spite of its widespread, continued usage, there are two very fundamental problems with CAPTCHA:
User experience: From a user standpoint, as just about anyone alive can tell you, the experience is a poor one. It’s time-consuming, increasingly difficult, and can often keep legitimate users from doing what they want and need to do.
Efficacy: From a security standpoint, quite simply, it doesn’t work. The challenge is supposed to be easy for users, and hard for bots, but in fact, it’s become quite the opposite.
Following is an overview of the plethora of options available that make it easy to bypass CAPTCHA challenges.
How Attackers are Easily Bypassing CAPTCHA Challenges
There are a number of CAPTCHA-solving technologies and services available to attackers today. Attackers choose the solvers that work best against the type of CAPTCHA used on a target site. Here are two high-level categories:
Automated Technologies and Plug-ins
There is a range of automated technologies, including APIs, browser plug-ins and extensions that enable attackers to bypass or solve CAPTCHA challenges. Here are a few examples:
A group of researchers from Lancaster University, Northwest University and Peking University used the concept of a generative adversarial network (GAN) in order to create an extremely fast and accurate CAPTCHA solver.
There are several free online CAPTCHA solving services and libraries that leverage deep learning-based technologies, including GRIS, Alchemy, Clarifai and NeuralTalk. Academic studies show that deep-learning-based approaches are highly accurate in solving CAPTCHA challenges.
DeCaptcher is an example of one of the solving services available via APIs making it easy to integrate into applications. Based on an optical character recognition system, the service solves challenges and provides a file to download that details the time, the challenge image, and the text used to solve the challenges.
Open-source tools and browser extensions, including Buster and UnCaptcha, use audio recognition that was intended to help visually impaired users and abuses it to bypass CAPTCHA mechanisms in an automated fashion.
Human-assisted Solving Services
In addition, there are also human-powered services that are available. These services are often staffed by people who work in so-called farms. These services are easy to find via a simple Google search. These services make it cost-effective for attackers to bypass the object recognition challenges used in reCAPTCHA.
2captcha and anti-captcha are some of the most popular examples of such a service. At a high level, these services enable customers to submit target websites, often via an API, to the vendor. The vendor’s staff will solve the challenge and provide the solution back to the customer. These vendors advertise solving 1, 000 regular CAPTCHA challenges for as little as $1. 00, and 1, 000 reCAPTCHA challenges for between $1. 99 and $2. 99.
Increasing Prevalence and Usage of CAPTCHA Solvers
Given their low/no cost, availability and efficacy, the use of CAPTCHA solvers continues to grow. With our PerimeterX Bot Defender solution, we’ve detected a rapid expansion in the use of CAPTCHA solvers. As the diagram below illustrates, between August 2019 and March 2020, we saw a significant increase in the volume of attempted attacks that employed CAPTCHA solvers.
Given their accessibility and ease, the use of CAPTCHA solvers has grown rapidly.
Conclusion
It’s abundantly clear that users and businesses can’t stand CAPTCHA mechanisms that interrupt the user flow and ultimately lower conversions on websites. Particularly as artificial intelligence continues to improve, standalone visual-challenge-response approaches aren’t viable. Quite simply, organizations can’t rely solely on CAPTCHA-based mechanisms to combat bots, given the abundance of CAPTCHA solvers. These realities are exposing a very clear demand for advanced mechanisms that don’t frustrate users and are difficult for bots to solve.
Frequently Asked Questions about how to recaptcha work
How does reCAPTCHA know I’m not a robot?
Instead of depending upon the traditional distorted word test, Google’s “reCaptcha” examines cues every user unwittingly provides: IP addresses and cookies provide evidence that the user is the same friendly human Google remembers from elsewhere on the Web.Dec 3, 2014
Does reCAPTCHA really work?
Efficacy: From a security standpoint, quite simply, it doesn’t work. The challenge is supposed to be easy for users, and hard for bots, but in fact, it’s become quite the opposite.Mar 26, 2020
How does invisible reCAPTCHA work?
According to Google, Invisible reCaptcha analyzes activity on a job post (e.g. mouse movements and typing patterns) to determine if a user is a robot. … Only the most suspicious traffic will be prompted to solve a captcha in order to submit an application.Apr 13, 2021