Hacking CAPTCHA Systems

Learn how to automatically break through a CAPTCHA system in this course.

7 videos  //  117 minutes of training

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Course description

The aim of this course is to implement and use a CAPTCHA-evading bot from scratch. In particular, we will cover the reconnaissance needed for this attack, the training and designing of the deep neural network to power the bot, using selenium to automate the CAPTCHA evasion, and finally, using the created bot on a webpage designed to be attacked.

Course syllabus

CAPTCHA BreakingDuration: 0:31

Sneak preview into writing a selenium bot to evade CAPTCHAs.

ReconnaissanceDuration: 3:53

Performing reconnaissance for the CAPTCHA breaking bot’s design.

Constructing a DatasetDuration: 8:56

Modifying the code of Really Simple CAPTCHA to generate a CAPTCHA image dataset.

Preprocessing the DatasetDuration: 24:03

Cropping and preprocessing the CAPTCHA dataset.

Training A Deep Neural NetworkDuration: 13:03

Train a deep neural network to identify the text of a CAPTCHA.

Building a CAPTCHA Breaking BotDuration: 6:25

Design a selenium bot to automatically evade CAPTCHAs.

Assignment - Fool MeDuration: 60:00

Create a bot that is able to automatically fill in the CAPTCHA at a target website.

Meet the author

Emmanuel Tsukerman


Dr. Tsukerman graduated from Stanford University and UC Berkeley. In 2017, his machine-learning-based anti-ransomware product won Top 10 Ransomware Products by PC Magazine. In 2018, he designed a machine-learning-based malware detection system for Palo Alto Network's WildFire service (over 30,000 customers). In 2019, Dr. Tsukerman authored the Machine Learning for Cybersecurity Cookbook and launched the Infosec Skills Cybersecurity Data Science Learning Path.

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