I just watched this episode this morning. I was thinking the same thing. It kind of went off the rails a bit. But the show is based off a comic book and the hacking in this episode is not the most far fetched thing they've done. I just laugh it off as entertainment.
Another show that uses quite a bit of over the top hacking in the plot is Scorpion[1]
Another show that uses quite a bit of over the top hacking in the plot is Scorpion[1]
[1] http://www.cbs.com/shows/scorpion/