Quantum Computing Bitcoin Attacks Could Happen Sooner Than Expected

The idea that quantum computing Bitcoin attacks could happen in the next decade is making some in crypto rethink security.

"Later" might be showing up a little sooner than expected. The idea that quantum computing Bitcoin attacks could happen in the next decade is making some in crypto rethink security. A recent breakthrough from Google’s Quantum AI team is putting a spotlight on what could happen when quantum computers get strong enough to break the encryption that forms the foundation of Bitcoin and other digital assets.

What Google Found

Right now, quantum computing Bitcoin threats are mostly theoretical, but experts say it’s time to start preparing. However, researchers at Google have been studying how quantum computers might eventually break modern encryption. Their latest findings? It might not take nearly as many quantum resources as we thought. They’ve found a way to break RSA-2048 encryption using 20 times fewer quantum bits (qubits) than previous models required.

Their latest findings? It might not take nearly as many quantum resources as we thought. They’ve found a way to break RSA-2048 encryption using 20 times fewer qubits than previous models required.

"A 2,048-bit RSA key could now be cracked in less than a week using fewer than 1 million noisy qubits, highlighting the rapid progress in this domain," said Google researcher Craig Gidney.

The researchers were able to factor a 72-bit number on a 49-qubit superconducting processor, showcasing the feasibility of breaking standard cryptographic keys with intermediate-scale quantum devices.

The researchers were able to factor a 72-bit number on a 49-qubit superconducting processor, showcasing the feasibility of breaking standard cryptographic keys with intermediate-scale quantum devices.

Now, Bitcoin doesn’t use RSA encryption, but it does rely on elliptic curve cryptography, which, like RSA, could one day be vulnerable to quantum attacks. If a strong enough quantum computer runs the right algorithm, like Shor’s algorithm, it could theoretically uncover a Bitcoin user’s private key just from the public information tied to a wallet.

Why This Matters For Bitcoin

Here’s the issue in plain terms: if someone can figure out your private key, they can move your coins. You don’t need to hand it over. They can just take it. That’s why people are suddenly talking about something called “Q-Day,” the moment quantum computers are strong enough to break the encryption protecting our digital assets.

Estimates for when Q-Day might arrive vary, but many experts say we’re probably within a 5 to 10-year window. That’s not tomorrow, but it’s definitely not “later” anymore.

This follows a warning by BlackRock, claiming that if quantum computers get powerful enough, they could threaten the security of Bitcoin and put people's funds at risk.

"If a third party gains access to a user's private key, they can transfer the user's Bitcoins out of the user's wallet without the user's consent or cooperation," BlackRock warned in its latest filing for a Bitcoin ETF.

Such a scenario could render current encryption useless, allowing quantum-powered attacks to siphon off coins and expose wallets.

Are We In Danger Now?

Not yet. The kind of quantum computers needed to pull this off still don’t exist, at least not at a scale that poses a direct threat. But Google’s research shows that we might be closer than expected, which means the crypto world can’t afford to ignore it.

Right now, only wallets that have exposed their public key are even remotely vulnerable, and most modern wallets are built to avoid that. Still, once a transaction is made, the public key becomes visible. That means old, unused addresses that haven’t moved coins in years could eventually become targets.

What’s Being Done About It?

Fortunately, people are already working on solutions. The U.S. National Institute of Standards and Technology (NIST) has been developing quantum-resistant cryptographic algorithms, and some are already being tested. Private companies like NordVPN have also started experimenting with quantum-safe encryption for internet traffic.

In the crypto space, upgrading to post-quantum security would be a big deal. It could require a hard fork, which means rewriting part of the network’s rules, and that’s not something the community takes lightly. But if the alternative is losing trust in Bitcoin’s safety, it’s a conversation that will need to happen.