Bitcoin Core before 0.19.0 might allow remote attackers to execute arbitrary code when another application unsafely passes the -platformpluginpath argument to the bitcoin-qt program, as demonstrated by an x-scheme-handler/bitcoin handler for a .desktop file or a web browser. NOTE: the discoverer states "I believe that this vulnerability cannot actually be exploited."

DISPUTED The Bitcoin Proof-of-Work algorithm does not consider a certain attack methodology related to 80-byte block headers with a variety of initial 64-byte chunks followed by the same 16-byte chunk, multiple candidate root values ending with the same 4 bytes, and calculations involving sqrt numbers. This violates the security assumptions of (1) the choice of input, outside of the dedicated nonce area, fed into the Proof-of-Work function should not change its difficulty to evaluate and (2) every Proof-of-Work function execution should be independent. NOTE: a number of persons feel that this methodology is a benign mining optimization, not a vulnerability.