Exploiting vulnerabilities in website databases to export user tables.
Even if the data is "private," the inclusion of addresses is significant. Because Google accounts often serve as the "master key" for a person’s digital life—linked to bank accounts, recovery emails, and cloud storage—a breach of these credentials can lead to total identity theft. How to Protect Yourself
This specific file name refers to a —a collection of over half a million email and password combinations (often called "combolists") frequently circulated in underground hacking forums and Telegram channels.
Using malware to grab passwords saved in browsers. The Risks for Users
Taking leaked data from one site and testing it against another (like Gmail).