Determining if at least 1 bit is set in the output of SHA256 Given the SHA256 hashing algorithm, is there any shortcut to determine whether 1 bit will be set in the output in a given position (or set of positions)? Relaxing the question a little bit, is there any probabilistic test (simpler than performing a full hash of course) to tell if a bit will be set (with probability 1) or not set (with probability &lt;1)?
No, the output of the hash is indistinguishable from random. If there was a shortcut to determine the value of an output bit given a certain input (other than executing the hash) then the hash would be broken.