Typo3 Extension "Accessible Form Captcha" vulnerabilities

The extension hides the correct answer to each CAPTCHA inside the image data of the CAPTCHA itself. Anyone who can request a CAPTCHA image can read the answer from it and submit it, so automated clients can pass the challenge. This applies to the default configuration, because the audio feature that causes the answer to be embedded is enabled by default. Forms that rely on the CAPTCHA as their only protection against automated submissions are exposed to abuse by bots.