2014 Yandex — 1.2M email passwords leaked
Data compromised
Email addresses, passwords
Technical writeup
Database of ~1.2 million Yandex email credentials (usernames and passwords) leaked and published on Habrahabr.ru. Yandex attributed breach to phishing/malware rather than direct server attack; claimed 85% were inactive or bot accounts.
Root cause
Phishing; credential assembly; disputed direct breach