---
id: 5501
title: "Cracking reCAPTCHA, Turbo Intruder style"
source_domain: portswigger.net
source_url: "https://portswigger.net/research/cracking-recaptcha-turbo-intruder-style"
published_at: "2019-11-20T15:33:00Z"
tags: ["bug-bounty", "web-security", "portswigger", "turbo-intruder", "race-condition", "bypass", "recaptcha"]
phying_url: "https://phying.com/item/5501"
lang: en
---

# Cracking reCAPTCHA, Turbo Intruder style

## Summary

James Kettle uses Turbo Intruder's last-byte synchronization to trigger a race condition that partially bypasses Google reCAPTCHA, demonstrated against Reddit after Google declined to fix it.

## Intelligence Metadata

- **Sources:** portswigger.net
- **Published:** 2019-11-20T15:33:00Z
- **Original:** https://portswigger.net/research/cracking-recaptcha-turbo-intruder-style
- **Phying News:** https://phying.com/item/5501