Thursday, April 17, 2025
HomeBotnetunCaptcha2 Bypassed Google ReCaptcha with 91% Accuracy

unCaptcha2 Bypassed Google ReCaptcha with 91% Accuracy

Published on

SIEM as a Service

Follow Us on Google News

Researchers from the University of Maryland recently break the Google’s
ReCaptcha audio challenge system using new unCaptcha2 with 91% of accuracy.

ReCaptcha is one the most popular system that protects website from bots and challenge that provides “I am not a robot” popups to make sure the website accessing by a real human.

This is one of the widely used system by millions of website in order to protect from bots and now its breaks second time using Google own
speech-to-text service.

- Advertisement - Google News

Earlier attempt on 2017, unCaptcha bypassed the ReCaptcha
digits chellange with 85% accuracy then later Google fixed and released an update.

Update contain some of the Major changes that includes Better browser automation detection and Spoken phrases rather than digits.

This was initially successful until the new unCaptcha2 break the new system on June 2018, and the unCaptcha2 bypass method shared to the
 Google ReCaptcha team.

unCaptcha2 Demo

unCaptcha2 basically using publicly available speech to text API in order to process the successful audio challenge to achieve 90% of accuracy.

It using a screen clicker to move to certain pixels on the screen and move around the page like a human.

According to the researchers, ” Since every users are different activities
unCaptcha2 has to go to specific coordinates on the screen , so based on the
your setup, coordinates  need to be updated.

There are 6 different simple unCaptcha2 approaches need to follow in order to achive the task.

  1. Navigate to Google’s ReCaptcha Demo site
  2. Navigate to audio challenge for ReCaptcha
  3. Download audio challenge
  4. Submit audio challenge to Speech To Text
  5. Parse response and type answer
  6. Press submit and check if successful

Users can use different speech-to-text API but you need to set your own credentials based on the API you choose.

In this case, some of the best speech-to-text API from Google’s, Microsoft’s, and IBM’s speech-to-text systems are already included in queryAPI.py.

“You’ll have to set the username and password as required; for Google’s API, you’ll have to set an environment variable (GOOGLE_APPLICATION_CREDENTIALS) with a file containing your Google application credentials.”

Now researchers released the code in GitHub since Recaptcha team is aware of this attack vector, and have confirmed they are okay with us releasing this code, despite its current success rate.

You can follow us on LinkedinTwitterFacebook for daily Cybersecurity updates also you can take the Best Cybersecurity courses online to keep your self-updated.

Balaji
Balaji
BALAJI is an Ex-Security Researcher (Threat Research Labs) at Comodo Cybersecurity. Editor-in-Chief & Co-Founder - Cyber Security News & GBHackers On Security.

Latest articles

Ransomware Attacks Surge 126%, Targeting Consumer Goods and Services Sector

The cybersecurity landscape witnessed a dramatic escalation in ransomware attacks, marking a concerning trend...

CrazyHunter Hacker Group Exploits Open-Source GitHub Tools to Target Organizations

A relatively new ransomware outfit known as CrazyHunter has emerged as a significant threat,...

Threat Actors Leverage Cascading Shadows Attack Chain to Evade Detection and Hinder Analysis

A sophisticated multi-layered phishing campaign was uncovered, employing a complex attack chain known as...

Microsoft Vulnerabilities Reach Record High with Over 1,300 Reported in 2024

The 12th Edition of the Microsoft Vulnerabilities Report has revealed a significant surge in...

Resilience at Scale

Why Application Security is Non-Negotiable

The resilience of your digital infrastructure directly impacts your ability to scale. And yet, application security remains a critical weak link for most organizations.

Application Security is no longer just a defensive play—it’s the cornerstone of cyber resilience and sustainable growth. In this webinar, Karthik Krishnamoorthy (CTO of Indusface) and Phani Deepak Akella (VP of Marketing – Indusface), will share how AI-powered application security can help organizations build resilience by

Discussion points


Protecting at internet scale using AI and behavioral-based DDoS & bot mitigation.
Autonomously discovering external assets and remediating vulnerabilities within 72 hours, enabling secure, confident scaling.
Ensuring 100% application availability through platforms architected for failure resilience.
Eliminating silos with real-time correlation between attack surface and active threats for rapid, accurate mitigation

More like this

Hacktivist Group Becomes More Sophisticated, Targets Critical Infrastructure to Deploy Ransomware

A recent report by Cyble has shed light on the evolving tactics of hacktivist...

New ‘Waiting Thread Hijacking’ Malware Technique Evades Modern Security Measures

Security researchers have unveiled a new malware process injection technique dubbed "Waiting Thread Hijacking"...

EU’s GDPR Article 7 Poses New Challenges for Businesses To Secure AI-Generated Image Data

As businesses worldwide embrace digital transformation, the European Union’s General Data Protection Regulation (GDPR),...