Quantum computer-based attacks, which have long been seen as a future threat to Bitcoin and have been ignored until now, have now become a more real risk. Project Eleven, a company working in the field of quantum security, announced that it gave the Q-Day reward worth 1 bitcoin to independent researcher Giancarlo Lelli. Using publicly available quantum hardware, Lelli cracked the 15-bit elliptic curve key and generated the private key from the public key.
Latest developments in quantum attacks
This reward, equivalent to approximately 78 thousand dollars, stands out as the largest quantum attack demonstration publicly held to date. The type of attack in question is at a level that can threaten not only Bitcoin but also most of the largest blockchain networks, including ether (ETH) in the future. Password-based wallets use the mathematics of elliptic curve cryptography to prove that they have the funds, and in this system, while a public key is visible to everyone, it is accepted that the private key cannot be obtained.
However, the quantum technique called Shor algorithm, introduced in 1994, fundamentally shakes this assumption. Despite Lelli’s result, Bitcoin is not expected to breakout immediately. Because Bitcoin’s security is based on a 256-bit elliptic curve, whereas the cracked key is only 15 bits. In other words, while one is looking for one of 32,767 possibilities, in Bitcoin this number is trillion times more.
Rapid progress in the race for hardware and research
Until seven months ago, the largest publicly available quantum code-breaking attempt was a 6-bit demonstration performed by IBM’s 133-qubit quantum computer. Lelli expanded this level by 512 times. Here, “bit” defines the basic unit in classical computers, and “qubit” defines the basic unit of information in quantum computers.
Theoretical calculations in this area are also progressing faster than expected. A study published last month by Google Research narrowed the number of physical qubits required for a full-scale 256-bit attack to under 500,000; Previous estimates put this figure in millions.
Project Eleven CEO Alex Pruden said, “The resources required for this type of attack are rapidly decreasing, and in parallel, the attack threshold is decreasing in practice.”
Concerns and precautions in the Bitcoin ecosystem
Pruden also pointed out that the winning application came from an independent researcher using cloud-accessible hardware, not a government lab or a special quantum chip. It is stated that approximately 6.9 million Bitcoins are held in wallets whose public keys are visible on the chain today. This is about a third of the total supply; Including 1 million untouched Bitcoins thought to belong to Satoshi Nakamoto.
If a quantum computer that can break the 256-bit elliptic curve is developed, these wallets may also be at serious risk. To reduce this risk, Bitcoin developers propose quantum-resistant address types, such as BIP-360. Ethereum, Tron, StarkWare, and Ripple have also released anti-quantum migration plans on their blockchains.
“A 15-bit key is still very small in real-life systems, but the developments have caused remarkable activity in the developer community and ecosystem across the industry,” it is commented.
As a result, it is stated that the 15-bit solution does not directly threaten Bitcoin, but practical experiments in quantum attacks are growing rapidly and theoretical limits are narrowing. These developments make the need for quantum security for blockchain-based assets even more visible.
