Stiltwalker is a proof of concept tool that defeats Google's reCAPTCHA with an insanely high accuracy (99%). We have released all of our research, code, tools and examples used in the reCAPTCHA domination. You can get the slides here and the video is at the bottom of the page.
We accomplished this with a combination of Machine Learning, hashing methods, keyspace reduction tactics, and taking advantage of an overall limited number of captchas. Specifically, Stiltwalker goes head to head against reCAPTCHA'S audio captcha system and defeats all but a sliver of it's challenges.
For all questions, comments, and fuckyous, please email the team at email@example.com
We developed everything using Ubuntu 10.04, Ubuntu 11.04, and Debian 6, however it should work on any Linux distribution without too much effort. The one thing we noticed when testing it on Ubuntu 12.04 is that it comes with a slightly different version of SoX, which has some changes which drops accuracy from 99% to around 60%. So for best results, you'll want to use SoX v14.3.0 (or v14.3.1), but we'd advice to steer clear of v14.3.2 unless you want to collect tens of