BleepingComputer writes: The text "HIBP" refers to the Have I Been Pwned data breach notification service created by Troy Hunt, with whom threat actors commonly share stolen data to be added to the service.

Hunt told BleepingComputer that the threat actor shared the Internet Archive's authentication database three days ago and it is a 6.4GB SQL file named "ia_users.sql." The database contains authentication information for registered members, including their email addresses, screen names, password change timestamps, Bcrypt-hashed passwords, and other internal data.

Hunt says there are 31 million unique email addresses in the database, with many subscribed to the HIBP data breach notification service. The data will soon be added to HIBP, allowing users to enter their email and confirm if their data was exposed in this breach.

https://www.bleepingcomputer.com/news/security/internet-archive-hacked-data-breach-impacts-31-million-users/