• Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
MUST READ

Cisco confirms active exploitation of ISE and ISE-PIC flaws

 | 

SharePoint under fire: new ToolShell attacks target enterprises

 | 

CrushFTP zero-day actively exploited at least since July 18

 | 

Hardcoded credentials found in HPE Aruba Instant On Wi-Fi devices

 | 

MuddyWater deploys new DCHSpy variants amid Iran-Israel conflict

 | 

U.S. CISA urges to immediately patch Microsoft SharePoint flaw adding it to its Known Exploited Vulnerabilities catalog

 | 

Microsoft issues emergency patches for SharePoint zero-days exploited in "ToolShell" attacks

 | 

SharePoint zero-day CVE-2025-53770 actively exploited in the wild

 | 

Singapore warns China-linked group UNC3886 targets its critical infrastructure

 | 

U.S. CISA adds Fortinet FortiWeb flaw to its Known Exploited Vulnerabilities catalog

 | 

SECURITY AFFAIRS MALWARE NEWSLETTER ROUND 54

 | 

Security Affairs newsletter Round 533 by Pierluigi Paganini – INTERNATIONAL EDITION

 | 

Radiology Associates of Richmond data breach impacts 1.4 million people

 | 

Fortinet FortiWeb flaw CVE-2025-25257 exploited hours after PoC release

 | 

Authorities released free decryptor for Phobos and 8base ransomware

 | 

Anne Arundel Dermatology data breach impacts 1.9 million people

 | 

LameHug: first AI-Powered malware linked to Russia’s APT28

 | 

5 Features Every AI-Powered SOC Platform Needs in 2025

 | 

Broadcom patches critical VMware flaws exploited at Pwn2Own Berlin 2025

 | 

Stormous Ransomware gang targets North Country HealthCare, claims 600K patient data stolen

 | 
  • Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
  • Home
  • Breaking News
  • Digital ID
  • Hacking
  • ReBreakCaptcha – How to breaking Google’s ReCaptcha v2 using Google’s APIs

ReBreakCaptcha – How to breaking Google’s ReCaptcha v2 using Google’s APIs

Pierluigi Paganini March 02, 2017

The researcher East-Ee Security devised a proof of concept bypass of the Google’s reCaptcha V2 verification system dubbed ReBreakCaptcha.

East-Ee Security proposed a proof of concept bypass of the Google’s reCaptcha V2 verification system dubbed ReBreakCaptcha. The PoC uses the Google web-based tools for its purpose. According to the author, ReBreakCaptcha “lets you easily bypass Google’s reCaptcha v2 anywhere on the web.”

The CAPTCHA (Completely Automated Procedures for Telling Computers and Humans Apart) service was devised to defeat bots and scripts that can be used to register thousands of accounts at a time.  ReCaptcha is the CAPTCHA solution proposed by Google that leverages image, audio or text challenges to verify the presence of a human while accessing the online service.

ReBreakCaptcha

The ReBreakCaptcha is able to byPass reCaptcha V2 via a script that leverages Google APIs to capture audio challenges as sound files.

The ReBreakCaptcha works in three stages:

  1. Audio Challenge – Getting the correct challenge type.
  2. Recognition – Converting the audio challenge audio and sending it to Google’s Speech Recognition API.
  3. Verification – Verifying the Speech Recognition result and bypassing the ReCaptcha.

The ReBreakCaptcha technique uses a way to get an audio challenge as part of the reCaptcha process.

“Some of you may notice that instead of an audio challenge, sometimes you get a text challenge,” reads the blog post published by the East-Ee Security researcher. “To bypass it and get an audio challenge, you simply click the ‘Reload Challenge’ button until you get the correct type.”

Once the ‘get an audio challenge’ option is selectes the reCaptcha allows the users to either play the audio file from the web page or download it.

“Let’s download the audio file and send it to Google Speech Recognition API. Before doing so, we will convert it to a ‘wav’ format, which is requested by Google’s Speech Recognition API. Now we have the audio challenge file and are ready to send it to Google Speech Recognition. How can this be done? Using (Google’s own) API,” continues the post.

Then the author sends the audio to the Speech Recognition that turns back the results in text format.

“We will send the ‘wav’ audio file and the Speech Recognition will send us back the result in a string (e.g. ‘25143’). This result will be the solution to our audio challenge,” East-Ee Security explains.

If you are interested in the ReBreakCaptcha technique, give a look at the Python-based proof of concept script available on GitHub.

[adrotate banner=”9″]

Pierluigi Paganini

(Security Affairs – reCaptcha , ReBreakCaptcha )


facebook linkedin twitter

Google Hacking ReBreakCaptcha reCAPTCHA

you might also like

Pierluigi Paganini July 22, 2025
Cisco confirms active exploitation of ISE and ISE-PIC flaws
Read more
Pierluigi Paganini July 22, 2025
SharePoint under fire: new ToolShell attacks target enterprises
Read more

leave a comment

newsletter

Subscribe to my email list and stay
up-to-date!

    recent articles

    Cisco confirms active exploitation of ISE and ISE-PIC flaws

    Hacking / July 22, 2025

    SharePoint under fire: new ToolShell attacks target enterprises

    Hacking / July 22, 2025

    CrushFTP zero-day actively exploited at least since July 18

    Hacking / July 22, 2025

    Hardcoded credentials found in HPE Aruba Instant On Wi-Fi devices

    Security / July 22, 2025

    MuddyWater deploys new DCHSpy variants amid Iran-Israel conflict

    APT / July 21, 2025

    To contact me write an email to:

    Pierluigi Paganini :
    pierluigi.paganini@securityaffairs.co

    LEARN MORE

    QUICK LINKS

    • Home
    • Cyber Crime
    • Cyber warfare
    • APT
    • Data Breach
    • Deep Web
    • Digital ID
    • Hacking
    • Hacktivism
    • Intelligence
    • Internet of Things
    • Laws and regulations
    • Malware
    • Mobile
    • Reports
    • Security
    • Social Networks
    • Terrorism
    • ICS-SCADA
    • POLICIES
    • Contact me

    Copyright@securityaffairs 2024

    We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies. However, you may visit "Cookie Settings" to provide a controlled consent.
    Cookie SettingsAccept All
    Manage consent

    Privacy Overview

    This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities...
    Necessary
    Always Enabled
    Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
    Non-necessary
    Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
    SAVE & ACCEPT