Hackaday Links: September 29, 2024

September 29, 2024 by Dan Maloney 16 Comments

There was movement in the “AM Radio in Every Vehicle Act” last week, with the bill advancing out of the US House of Representatives Energy and Commerce Committee and heading to a full floor vote. For those not playing along at home, auto manufacturers have been making moves toward deleting AM radios from cars because they’re too sensitive to all the RF interference generated by modern vehicles. The trouble with that is that the government has spent a lot of effort on making AM broadcasters the centerpiece of a robust and survivable emergency communications system that reaches 90% of the US population.

The bill would require cars and trucks manufactured or sold in the US to be equipped to receive AM broadcasts without further fees or subscriptions, and seems to enjoy bipartisan support in both the House and the Senate. Critics of the bill will likely point out that while the AM broadcast system is a fantastic resource for emergency communications, if nobody is listening to it when an event happens, what’s the point? That’s fair, but short-sighted; emergency communications isn’t just about warning people that something is going to happen, but coordinating the response after the fact. We imagine Hurricane Helene’s path of devastation from Florida to Pennsylvania this week and the subsequent emergency response might bring that fact into focus a bit.

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Stiltwalker Beat Audio ReCAPTCHA

June 15, 2012 by Mike Szczys 13 Comments

This talk from the 2012 LayerOne conference outlines how the team build Stiltwalker, a package that could beat audio reCAPTCHA. We’re all familiar with the obscured images of words that need to be typed in order to confirm that you’re human (in fact, there’s a cat and mouse game to crack that visual version). But you may not have noticed the option to have words read to you. That secondary option is where the toils of Stiltwalker were aimed, and at the time the team achieved 99% accurracy. We’d like to remind readers that audio is important as visual-only confirmations are a bane of visually impaired users.

This is all past-tense. In fact, about an hour before the talk (embedded after the break) Google upgraded the system, making it much more complex and breaking what these guys had accomplished. But it’s still really fun to hear about their exploit. There were only 58 words used in the system. The team found out that there’s a way to exploit the entry of those word, misspelling them just enough so that they would validate as any of up to three different words. Machine learning was used to improve the accuracy when parsing the audio, but it still required tens of thousands of human verifications before it was reliably running on its own.

Continue reading “Stiltwalker Beat Audio ReCAPTCHA” →

Are You Human? Then Type Out This Book

September 18, 2009 by Mike Szczys 52 Comments

type_this_text

Google has acquired reCAPTCHA and plans to use the system for digitizing books. Wait… what? CAPTCHA is the method of requiring a user to type in a visually obscured word to prove they are human. How can this digitize books? The answer is a bit obscure and takes some time to discover, but you’ll have fun along the way. Continue reading “Are You Human? Then Type Out This Book” →

Time’s Poll Hacked

April 29, 2009 by Caleb Kraft 50 Comments

res4

Though Time won’t admit it, their poll on the most influential person was hacked. Moot, the founder of 4chan is rated #1. Not only that, but if you read the first letters of the poll results, you get “Marblecake also the game”. This refers to the IRC Chanel where many 4channers congregate as well as “the game” an internet meme. This article is very interesting as it delves into the details of the attack. Focusing mainly on what happened when the autovoting software was shut down due to reCaptcha. you’ve probably seen reCaptcha before. It presents you with two words, made difficult to read by strange kearning, warping, and squiggles. If you can read it, you’re most likely a human. Anon, a common name for 4channers, first tried to hack reCaptcha.

Their attempt at hacking reCaptcha relies on the process reCaptcha uses to identify words. It presents you with two words, one of which it already knows. The other is compared to a database of common responses to that word. Anon decided that if they entered “penis” enough times, they could flood the database allowing their autovoter to function again. This, though clever, was unsuccessful. They eventually settled on manual voting. This was taking too much time, they feared they would never reach their goals. To help with this, they built a simple interface that would preload several reCaptchas and cue up votes. This streamlining allowed them to squeak in the votes they needed to accomplish this.

It’s also worth noting that Time didn’t close the vote entries when the poll closed. They removed the poll from their site, but the streamlined vote software was still working. Anon is a powerful force of nature. If only we could harness it to cure cancer or HIV.

MegaUpload Captcha Cracking In JavaScript

January 23, 2009 by Eliot 25 Comments

This was certainly the last thing we expected to see today. [ShaunF] has created a Greasemonkey script to bypass the captcha on filehosting site Megaupload. It uses a neural network in JavaScript to do all of the OCR work. It will auto submit and start downloading too. It’s quite a clever hack and is certainly helped by the simple 3 character captcha the site employs. Attempting to do the same thing with ReCAPTCHA has proven much more difficult.

UPDATE: [John Resig] explained of how it works.

[via Waxy]