A folder with over 12,000 files containing nearly 773 million email addresses and over 21 million unique passwords from numerous previous data breaches — some potentially dating back to 2008 — has been posted online in another massive leak of credential data.

Security researcher Troy Hunt discovered the 87 GB worth of data on cloud storage service Mega last week and has uploaded it to his Have I Been Pwned (HIBP) service, where individuals can verify if their email addresses are on the list. The leaked passwords, meanwhile, have been published on Pwned Passwords, a site that Hunt maintains to let people check whether their passwords have been exposed in data breaches.