Yandex company blog

Mail Encryption in Yandex.Mail

With the data privacy issues making front pages around the world, Yandex.Mail emails are passed from user’s device to the Yandex.Mail server, from the Yandex.Mail server to the receiving mail server and to their final destination on the addressee’s device, in safety. Messages sent or received by over 50 million users of the service are now securely protected from tapping into during a server-to-server transfer by encryption.

Opportunistic encryption protects data during transfer between internet users by encrypting it in one or more segments of the route, depending on encrypting capabilities of each party. If one of the messaging systems supports encryption, while the other one doesn’t, data transfer takes place anyway, albeit unencrypted.

Historically, electronic messaging services developed as desktop computer programs – email clients, which accessed and transferred user’s emails using Internet Message Access Protocol (IMAP), Post Office Protocol 3 (POP3) and Simple Mail Transfer Protocol (SMTP). These days, the majority of emails around the world is sent and received via web-based email services, which use a common data communication protocol, Hypertext Transfer Protocol (HTTP). These protocols are used to pass information from sender to sender’s mail server, from sender’s mail server to receiver’s mail server, and then to access this information on receiver’s mail server and pass it on to receiver. These protocols don’t offer data encryption and require an extension to convert plain text to an encrypted form.



Yandex.Mail, one of Russia’s most popular email services, whose users send about 15 million messages and receive about 100 million messages every day, is now using cryptographic protocols Transport Layer Security (TLS) and Secure Sockets Layer (SSL) to provide secure communication between Yandex.Mail servers and the servers of other email systems. The service has been encrypting communication between users’ browsers and its servers since 2011, while data transfers between mailing clients and Yandex.Mail servers has been encrypted starting from 2009. All mobile versions of Yandex.Mail are shipped to end users with encrypting capabilities.


About 30% of all messages coming to Yandex.Mail servers are protected by encryption. We are always happy to see the messages in Yandex.Mail that arrive encrypted at each point of their path – from the sender’s browser to the sender’s mailing server using HTTPS to our mailing server using TLS over SMTP. This means that someone cares about people’s right for privacy as much as we do.