A file containing about 10 billion individual passwords was posted on an online hacking forum in what could be the largest such compilation of leaked passwords ever. The file was posted on July 4, and contains passwords compromised in both recent and old data breaches all over the world.

So many passwords available to hackers increases the likelihood of credential stuffing attacks, where one compromised password used for a user’s account can be reused by a hacker to break into another account. The list’s discovery is a reminder to use unique, strong passwords for each account in a person’s name.