Suppose I have an HD public xpubkey and I derive bitcoin public address(es) from it.
Given one of the public bitcoin address derived from it e.g.
1F1tAaz5x1....Can you get the xpubkey e.g.
xpub6DKUi1BvKEgn...I thought it is impossible, but someone I know claims it is possible.
And if it is possible isn't the privacy compromised in this situation?
Not sure if this is directly related but also take a look at
Deterministic Wallets, Their Advantages and their Understated Flaws (
"An Understated Problem" section):
https://bitcoinmagazine.com/articles/deterministic-wallets-advantages-flaw-1385450276/You cannot derive a key (public or private) from an address because an address is a hash (plus version byte and checksum).
Perhaps you are confusing that with a different issue: you can derive the master private key from the master public key and a child private key.