Here, we'll discover the snapshot attack on encrypted filesystems. This has application to off-site encrypted backup storage, such as Iron Mountain or Amazon S3. We'll learn how the attack works, with visual examples, as well as how to thwart the attack effectively. Although the presentation will be presented on GNU/Linux, this attack is generic, and works with any encrypted filesystem, including TrueCrypt, VeraCrypt, Bitlocker, LUKS, and all the others.