I wrote "script kiddie" as a way to describe the relative complexity of this attack vector - I was highly impressed with the pentest process, and think it's one of the smartest things we did this quarter.

Filtering user inputs is security 101, yet we missed this while focusing on fancy defense mechanics. This large gap between what the engineering team prepared for, and how they were exposed, is what made the outcome "embarrassing" - hence I agreed with GP that CSV/Excel stuff could be a blind spot even for well-trained people.