The premise that a Bitcoin wallet has been hacked is incorrect; independent researcher Giancarlo Lelli recently cracked a 15-bit elliptic curve encryption key using a quantum computer, earning a 1 $BTC bounty from Project Eleven, but this did not involve stealing actual Bitcoin or compromising the network's security.
Bitcoin relies on 256-bit elliptic curve cryptography, which is exponentially more complex than the 15-bit key Lelli compromised; the gap between 15 bits and 256 bits represents a difficulty factor of approximately 2^241, meaning current quantum hardware is nowhere near capable of breaking real-world Bitcoin wallets.
While Lelli’s achievement using a variant of Shor’s algorithm on cloud-accessible hardware marks the largest public demonstration of this attack class to date, it is a theoretical milestone rather than an immediate threat.
Approximately 6.9 million BTC in wallets with exposed public keys may be vulnerable to future quantum attacks, but experts estimate that building a quantum computer capable of breaking 256-bit encryption will require 10,000 to 500,000 physical qubits, a threshold not yet reached.
https://www.coindesk.com/tech/2026/04/24/researcher-wins-1-bitcoin-bounty-for-largest-quantum-attack-on-underlying-tech