Some of the data in chevereto is considered to be sensitive data. So it is encrypted.
Encryption is good, but adding a salt to an encryption is even better because it add another layer of security unique for your application.
So, when you encrypt data, it add your unique salt to the encryption, instead of a salt shared by every Chevereto clients.
You can find it in includes/definitions.php and edit it to a secret value you decided.
Once this value is decided, never edit it again, otherwise you won't be able to decrypt your data.