As a top ranked bug bounty researcher and Sr. Penetration Tester, I’ve discovered some critical vulnerabilities without ever directly accessing or scanning the target in question. These vulnerabilities are typically found by querying 3rd party services to discover cached and historic URL’s from a target and searching interesting URL’s. In some cases, this has lead me to discover critical “0day” vulnerabilities in commercial security products, Corporate owned websites and online services. In this blog post, I’ll discuss the methodology and step-by-step process used to find these vulnerabilities and how we can leverage tools like Sn1per Professional to assist us.