BTSec
Date
Description
In September 2014, a large dump of nearly 5M usernames and passwords was posted to a Russian Bitcoin forum. Whilst commonly reported as 5M "Gmail passwords", the dump also contained 123k yandex.ru addresses. Whilst the origin of the breach remains unclear, the breached credentials were confirmed by multiple source as correct, albeit a number of years old.
Amount of leaked user accounts
4789599
Leaked Data
Email addresses, Passwords