These databases are frequently sold or shared on dark web forums and Telegram channels for several purposes:

Accessing AOL accounts to send out mass phishing emails from "trusted" addresses.

Never reuse passwords. Use a Password Manager (like Bitwarden or 1Password) to generate and store unique credentials for every site [2].

Use a service like Have I Been Pwned to see if your email address has appeared in known data breaches.

Automated bots use these lists to try and log into other services (like banking, Netflix, or Amazon) assuming users reuse the same password across multiple sites [3, 4].

In the world of data security, a "combo list" is a collection of leaked credentials harvested from various data breaches [1, 3].

Specifies that the credentials are specifically for AOL email accounts. 2. How These Lists are Used