Mail.ru Data Breach 5M Compromised Accounts Leaked.

In September 2014, several large dumps of user accounts appeared on the Russian Bitcoin Security Forum including one with nearly 5M email addresses and passwords, predominantly on the mail.ru domain. Whilst unlikely to be the result of a direct attack again mail.ru, the credentials were confirmed by many as legitimate for other services they had subscribed to.

Compromised data: Email addresses, Passwords