Breach date: 2012-03-22. Added to this index: 2016-09-20. Accounts affected: about 37M. Domain: last.fm.
What happened
In March 2012, the music website Last.fm was hacked and 43 million user accounts were exposed. Whilst Last.fm knew of an incident back in 2012, the scale of the hack was not known until the data was released publicly in September 2016. The breach included 37 million unique email addresses, usernames and passwords stored as unsalted MD5 hashes.
Breach data sourced from Have I Been Pwned, used under CC BY 4.0. Additional breach metadata provided by XposedOrNot. DataExposed is an independent service and is not affiliated with or endorsed by either.
What was exposed
Email addresses: The email address you used to register or log in. It is the most common field in breaches because it doubles as your username on most sites.
Passwords: The secret you use to sign in, stored by the breached service either in plain text, in a scrambled form called a hash, or encrypted. How it was stored decides how quickly it can be recovered.
Usernames: The handle or login name you chose for an account, which may be public on forums, games and social platforms or used privately to sign in.
Website activity: Records of your actions on a website or app, such as pages viewed, searches, clicks, downloads, logins, cart activity, IP addresses and timestamps.
What to do now
Check whether your own address is in this dataset with the free email breach check.
Change the password on this service and every other site where you used the same password.
Turn on two-factor authentication on your email account first, because it is the reset path for everything else.
Treat calls and messages that quote real details about you as hostile until you verify them another way.
Frequently asked questions
What data was leaked in the Last.fm breach?
The Last.fm breach exposed Email addresses, Passwords, Usernames, Website activity. About 37M accounts were affected.
Was I affected by the Last.fm breach?
Run the free email breach check with the address you used on that service. It will tell you whether your address appears in this dataset.
What should I do about the Last.fm breach?
Change the password on that account and everywhere you reused it, then turn on two-factor authentication. Passwords from this breach are traded and tried automatically against other sites.