0xB9's Vulnerability Follow-Ups

I found one of the quickest vulnerabilities I think I will ever find right after signing up for an account on the website. This was a private bug bounty program so I will not be disclosing the company name, but I think you will still find this quite interesting! As mentioned in the title, it was just an Open Redirect so it wasn’t the biggest reward in the world, but it was well worth it considering how quickly I found it!

It all started when I was invited to the private program and saw the invitation in my email. A few days later I didn’t see any reports accepted for the program yet so I decided to take a look for myself. I first took a look at the application and what the website was running on with Wappalyzer. If you aren’t using this for analyzing websites, I would highly recommend checking it out as it can give you loads of information about the website.

After analyzing the website with Wappalyzer I didn’t come across anything interesting so I decided to move on and create an account on the website to see what it had to offer… Upon creating an account, I noticed I was prompted to fill out a quick form about my interests. I quickly noticed the URL was the following… https://example.com/welcome?redirectLink=https://example.com

Immediately after seeing the URL I did the obvious and entered https://example.com/welcome?redirectLink=https://google.com into my browser but unfortunately, I wasn’t redirected anywhere. I then proceeded with the form and BOOM! I was redirected to Google.com after completing the form. This form was also able to be completed an unlimited amount of times, so the possibility to use it for phishing was even higher.

And that’s the story of my quickest bug bounty I have ever found, hope you enjoyed!