unCaptcha

Health v2 · maintenance only

Flags: no_releases no_license

Adoption not part of the score

4917 stars · 449 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

unCaptcha2 is a Python-based security research tool that defeats Google's ReCaptcha v2 audio challenges by submitting the audio to free speech-to-text APIs and automating screen clicks, achieving roughly 90% accuracy. It was developed as academic research at the University of Maryland and released with Google's knowledge after responsible disclosure.

Use cases

• demonstrate weaknesses in recaptcha audio challenges
• security research on captcha systems
• test captcha defenses on sites you control
• study speech-to-text abuse in automated attacks
• educational demonstration of low-resource captcha attacks

When to choose

• you are a security researcher studying captcha vulnerabilities
• you need a reference implementation of audio captcha attacks for academic work
• you want to test your own site's captcha deployment

When to avoid

• you need a maintained or supported tool - it is unmaintained since 2019 and ReCaptcha has since changed
• you want to bypass captchas on sites you do not own - that is unethical and often illegal
• you need a production-ready automation framework - coordinates must be manually configured per setup

Facets

cli-tool · maturity abandoned

speech-recognition security penetration-testing security speech-processing artificial-intelligence python captcha-solving recaptcha security-research screen-automation academic-research linux desktop

Member repositories

For agents

markdown · JSON · MCP: product_card(name="ecthros/uncaptcha2")