What do the folders "d" and "m" mean? What is the .bkup file?


I’d like to know what exactly is the folders d and m and .bkup file does. Is the vault is only .cryptomator file or all of the files? I’d appreciate if someone can answer me

Created Vault via Cyberduck - bkup-File is missing. A problem?
Masterkey Backup File

The folder d stands for “data”. This is where your encrypted files are stored.

The folder m stands for “metadata”. This is currently only used for name shortening.

The .bkup file is a backup of your masterkey file. It’s created after every successful unlock.

Everything is part of the vault and you shouldn’t rename/move/delete anything.

Files in Folder "m" are changing very frequently and very often

Wouldn’t it be easily modified/destroyed as the data files are visible


Encryption protects your privacy, it doesn’t make data indestructible. That is what backups are for and cloud storage is (mostly) good at.

Modifying files will break their HMACs, so decrypting tampered files will fail. I.e. attackers can not secretly modify contents or file names.


apologies for this newbie question: why are these crypto files .bkup and .cryptomator stored on the cloud drive while the vault is open? if someone gets access to the cloud then they can use these files to decrypt the contents??


No. The password of the vault is required.