After the Affordable Care Act went into effect I signed our company up for our state's marketplace. While browsing our plan options, I noticed the url used a scheme like marketplace.org/employers/341/plans.aspx. Of course, I tried changing the number in the url to 342 to see what happened. To my astonishment, it loaded up the next company's plans, including a list of employee names, ages, plan cost, and SSNs.
After I shopped a few other companies to see how our plans compared, I notified the marketplace operator via the only link on the website for customer service. Within about an hour, someone from their IT department rang me on the phone and started grilling me about how many other plans I browsed, and insisted that I clear my cache and browsing history, and notified me that they would be watching to make sure nobody at our IP address didn't access any other plans while the issue was being fixed.
I was pretty surprised at his response, and assumed they would be more grateful for exposing a pretty basic flaw, but I guess a natural human tendency in these situations is to try to externalize the blame. Perhaps it's more difficult to hold yourself accountable than it is to assume that others who've found your shoddy work are malicious actors.