Without any sort of formally posted bug bounty program explicitly authorizing this sort of activity the CFAA prohibits unauthorized access of "protected computers". I would classify this as legally risky. If FIA had a stick up their ass they could definitely come after the researcher. The researcher's ethical standing is pretty clean in my book, but this was definitely a little more than just changing a URL parameter (only a little more). I would say this is unsafe to do if you are in the united states. The stopping point was somewhere around "I think I could provide the admin role" and reaching out to the best contact you can find and say "Hey, I am an ethical white hat security researcher and I noticed X and Y and in my experience when I see this there is a pretty reasonable chance this privilege escalation vulnerability exists. The chance it exists is high enough in my experience that you should treat it like it exists and examine your authorization code. If you would like I can validate this on my end as well if you give me permission to examine this issue. I am an ethical security researcher" ---> point over to your website and disclosed issues if you got em. To just do it is ehh... I would not take the risk. However if I /did/ do it I would definitely disclose it to them immediately and give an explanation like the above. Shooting the messenger in this case would be pretty asinine, especially if they didn't access anything sensitive, that would preclude FIA from having any evidence you did anything sketchy (cause you did not). The reason I would not do it is because you never know if a system like this pre-fetches data, etc. and that is definitely opening you up to liability of possessing PII etc. Overall, I have disclosed issues like this in the past without actually exploiting the issue to good results. Some times companies ignore it. You can always say "If you do not want to treat this issue as a vulnerability I am going to write this up on my website as an example of things you should probably not do" if you feel ethically compelled to force them to change without actually exploiting the issue. People tend to get the message and do something.