Secure CAPTCHA with Patch Base Defense

Vinayak PatilDepartment of Computer Engineering, P.S.G.V.P. Mandal’s D.N. Patel College of Engineering, Shahada, Maharashtra, IndiaPunit PatilDepartment of Computer Engineering, P.S.G.V.P. Mandal’s D.N. Patel College of Engineering, Shahada, Maharashtra, IndiaLokesh PatilDepartment of Computer Engineering, P.S.G.V.P. Mandal’s D.N. Patel College of Engineering, Shahada, Maharashtra, IndiaDinesh PatilDepartment of Computer Engineering, P.S.G.V.P. Mandal’s D.N. Patel College of Engineering, Shahada, Maharashtra, IndiaPiyush PatilDepartment of Computer Engineering, P.S.G.V.P. Mandal’s D.N. Patel College of Engineering, Shahada, Maharashtra, India

Vol 10 No 5 (2026): Volume 10, Issue 5, May 2026 | Pages: 345-352

International Research Journal of Innovations in Engineering and Technology

OPEN ACCESS | Research Article | Published Date: 17-05-2026

doi Logo doi.org/10.47001/IRJIET/2026.105045

Abstract

In the modern digital era, automated bots and malicious scripts have become a major threat to online platforms. Traditional CAPTCHA systems are increasingly vulnerable to machine learning attacks. This project proposes an Adversarial CAPTCHA Security System using Generative Adversarial Networks (GANs) and deep learning techniques to improve CAPTCHA robustness against automated bots. The system generates adversarial CAPTCHA images by adding GAN generated perturbations to real images from the CIFAR-10 dataset. These adversarial images remain understandable for humans while making automated recognition difficult for bots. The system also includes secure user authentication using Flask and SQLite database integration. Experimental results demonstrate improved CAPTCHA security and enhanced resistance against automated attacks.

Keywords

GAN, CAPTCHA, Deep Learning, CIFAR-10, Adversarial Images, Flask, SQLite.


Citation of this Article

Vinayak Patil, Punit Patil, Lokesh Patil, Dinesh Patil, & Piyush Patil. (2026). Secure CAPTCHA with Patch Base Defense. International Research Journal of Innovations in Engineering and Technology - IRJIET, 10(5), 345-352. Article DOI https://doi.org/10.47001/IRJIET/2026.105045

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