Amazon May Have Plan To Help Alexa Fight Fake Voice Attacks

a patent application posted on January 10 by Amazon that looks like Alexa’s parent company has figured out a new way to detect replay attacks in voice-based authentication systems.
A replay attack is a form of network attack in which valid data transmission is maliciously or fraudulently repeated or delayed — this is also sometimes known as a playback attack or a “man-in-the-middle” attack.