%% Last Updated: - [[2021-02-25]] - [[2020-09-12]] %% PGP stands for Pretty Good Privacy, and it is a way to encrypt a message without having had previous communication with the intended recipient. In PGP, a message is encrypted several times with different keys: - First, a session key is generated, and the request payload is encrypted with the session key to prevent man-in-the-middle attacks. - Next, the session key itself is encrypted with multiple keys or passwords provided by the user, and each encryption is sent as a separate packet. ## References - [[The ProtonDrive Security Model - ProtonMail Blog]]