Our industry (area of cheap networked devices) has a standard that defines the usage of keys for both authentication and encryption using EAX mode of AES. This standard does not define key management, and someone wants to change this key material in devices using the RFC 3394 key wrap algorithm. For that they want to use these very same encryption/authentication keys as key-wrapping keys to receive new keys (no separate/master key-wrap-key).
I assume it is a bad idea, but I could not find a clear prohibition for this, and here is the best I could find on this site. Can anyone help with a better reference/book? Or is that safe after all?