Researcher Breaks ReCAPTCHA Using Google's Speech Recognition API

An anonymous reader writes: "A researcher has discovered what he calls a "logic vulnerability" that allowed him to create a Python script that is fully capable of bypassing Google's reCAPTCHA fields using another Google service, the Speech Recognition API," reports BleepingComputer. The attack is incredibly simple and works by downloading a version of the reCAPTCHA audio challenge, feeding it into Google's Speech Recognition API, getting the text-version of the audio challenge, and feeding it back into the reCAPTCHA field. Proof-of-concept code is available on GitHub, and the researcher says Google has failed to patch the issue, albeit it's unclear if he ever notified the company. The attack also only works against reCAPTCHA v2, not other versions like v1, or the upcoming Invisible reCAPTCHA (v3). Because the source code for the exploit is available online, security experts expect to see it ported to JavaScript and used to create browser extensions that bypass reCAPTCHA fields, especially when using the Tor Browser.