There's an easy way to find out. If you enter your log-in ID on Troy Hunt's "Have I been pwned" website, the site will tell you if you have an account that was compromised in a data breach. Yes, it is a safe site (not all are). Troy Hunt is a Microsoft Regional Director and Most Valuable Professional awardee for Developer Security, blogger at troyhunt.com, international speaker on web security and the author of many top-rating security courses for web developers on Pluralsight.
You probably use your e-mail address a lot as well as your name, etc. when creating an account ID – those are obvious places to start.
No one is immune – John and I have both been compromised – by the Adobe, Dropbox and LinkedIn breaches. It's a pain, but better to change your credentials, not only where you've been compromised but on other sites using the same ID, especially if you reuse passwords, as indeed most people do.
A very handy tool – and one of our favorite technology tips.
E-mail: firstname.lastname@example.org Phone: 703-359-0700
Digital Forensics/Information Security/Information Technology