The NAS-4220-B offers disk encryption through it's web interface. The key used for encrypting the disk(s) is stored on a unencrypted partition. Therefore one can extract the encryption key by removing the disk from the Raidsonic NAS-4220 and reading the value from the unencrypted partition. The key itself is stored in a file in plain (base64 encoded). Therefore the NAS-4220 crypt disk support can not be considered secure.
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