Tools: I Spent Two Minutes Testing Amazon’s API. It Was Enough.

There’s something oddly comforting about large tech companies. You assume that somewhere, deep in the labyrinth of their infrastructure, there are teams of very serious engineers making sure everything behaves exactly as it should. So when I decided to test one Amazon endpoint, I picked the most boring one I could find. Not payments. Not checkout. Not anything involving money. All it does is update a child profile name. You send "name": "Kids3", and life goes on. Or at least, that’s the theory. I captured the real browser request, pasted it into Rentgen, pressed run, and went to make coffee. Two minutes later I had a certificate score: 16 out of 100. Now, this wasn’t a penetration test. I didn’t try to break the system. I didn’t throw SQL injections at it. I didn’t spin up some exotic fuzzing setup. I just asked very boring questions. What happens if authentication is missing?
Apparently not 401 — but 400. With a generic “Sorry, we are experiencing issues right now.” Which is comforting, in the same way that a smoke alarm yelling “Something is wrong somewhere” is comforting. What happens if you use an unsupported HTTP method?
You get 403. As if the method exists but you’re not important enough to use it. What happens if you uppercase the path?
You get HTML. Yes. A full CloudFront “Website Temporarily Unavailable” page — from a JSON API. Because apparently, sometimes your structured contract just takes the day off. And then the fun one: send a 10MB payload. Not malicious. Just large. Instead of a clean 413 Payload Too Large, the request travels deep enough into the stack to come back confused with a 404. All of this. From renaming a child profile. This isn’t about “Amazon is broken.” It’s about what happens when systems grow faster than their contract discipline. Status codes drift. Edge layers leak. Validation happens too late. The scary part isn’t that these things exist. It’s how quickly they surface when you look. Full breakdown here:
https://rentgen.io/api-stories/amazon-profile-update-api-testing-case-study.html Automation before automation. Find API bugs when you have no tests. Templates let you quickly answer FAQs or store snippets for re-use. Are you sure you want to hide this comment? It will become hidden in your post, but will still be visible via the comment's permalink. Hide child comments as well For further actions, you may consider blocking this person and/or reporting abuse CODE_BLOCK:
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