Seriously as others have pointed out thats NOTHING. Anyone can do this to pretty much any device, I did that to my ISP's router even and don't feel its any less secure because of it. Its an interesting hack but its not proof of any insecurity of Alexa.

I don't think its such a good idea to over-dramatize these things for personal gain (like the author) because it hurts the security researcher community as a whole. I've already lost ANY trust of any security guys talking about the end of the world vulnerability they found, 99% of the time its bullshit like this. But I can read their disclosure and quickly discern whats irrelevant, I can imagine most non-IT people not able to do this and thus becoming MUCH more desensitized to ACTUAL vulnerabilities. Yet another boy who cried wolf security guy, they should've published this as "how to root your alexa" that would've been actually cool, this is just garbage.