I just found a security breach that can leak thousands of emails on a website!!
Today, I snooped around on a website I won’t mention the name of for privacy reasons, and they assign your account an user ID when you register.
Well, with a very simple trick in the console I managed to get everyone else’s email and account info (for example checking if they have a paid plan or not) by just lowering the user id, with no rate-limit on the endpoint!
So a bad actor could send targetted phishing emails to people by telling them there is a problem with their payment!
It’s funny because on their homepage, they state they use “Military grade encryption” (whatever that means!), and their privacy policy says “We encrypt the transmission of that information” (does that just mean they do it over https?)
So, moral of the story, don’t trust companies with your personal info!
I contacted the site, we’ll see if they fix it.
Based on the description this seems to be improper authorisation. An authenticated user can access data that it’s not supposed to (I assume you need to log in to see the data). The site in question should have a security contact where you can send your proven finding. Something like security@company.com or cert@company.com. They will usually require GPG encryption so the misconfigurstion you are reporting is not snooped (the attachment should be enough).
Make sure you check for a security.txt file (typically
/.well-known/security.txt), they should have the most up-to-date information in there.