Use services like Have I Been Pwned to see if your email has been part of a known breach.

These lists are often compiled from multiple data breaches or via "stealer" malware.

They are frequently shared or sold on underground forums and Telegram channels for account cracking (e.g., streaming services, gaming accounts, or retail sites). Security Risks Possessing or using such a file carries significant risks:

These files are generally used for , where automated tools attempt to log into various websites using leaked data from previous breaches.