security - Can the SHA-256 hash be derived from the SHA-512hash of the same data? -

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i applying sha-512 on data. theoretically/practically possible derive sha-256 hash original data sha-512 hash?

since have different number of rounds, different size of internal state , different block-size i'm pretty sure result of sha-256 , sha-512 different can't derive either of them other.

but if paranoid append/prepend different data different hash-functions. i.e. calculate sha-256("a"+data+"b") , sha-512("d"+data+"e") (of course longer strings instead of abcd).

the possibility see if set of possible input values small brute-force possible values until hit known hash , calculate other hash. if conditions attacker can reverse known hash, can calculate other hash.


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