Russian internet and search company Yandex announced today that one of its system administrators had enabled unauthorized access to thousands of user mailboxes. The company discovered the breach internally, during a routine check of its security team. The employee s actions led to the compromise of almost 5,000 email inboxes. The total number of inboxes compromised this way amounts to 4,887. In a press release today, the company said that the administrator did it for personal gain suggesting that they had a financial motivation.
Source: https://www.bleepingcomputer.com/news/security/yandex-suffers-data-breach-after-sysadmin-sold-access-to-user-emails/