Cyberattack on Liquid: 4,000 BTC Stolen While Bitcoin Remains Intact

The hack of the Liquid network that emptied 4,000 BTC was not against Bitcoin

Bitcoin has not been hacked. What was attacked is Liquid, Blockstream's Bitcoin sidechain. The loss, however, is significant: 4,000 BTC, approximately $320 million, withdrawn from the network's reserves. The attacker claims, according to available information, to be an ethical hacker willing to return the funds once the vulnerability is corrected. The network has been paused. And the prevailing question is whether this invalidates the supposed security of cryptocurrencies. Not by a long shot, but it warrants explanation.

What is Liquid and why is it not the same as Bitcoin?

Liquid is a sidechain, a secondary layer built on top of Bitcoin. It allows for faster and more private transactions, as well as the issuance of other assets. To participate, you deposit bitcoins into a wallet controlled by a federation and receive L-BTC in a 1:1 ratio. When you wish to return to Bitcoin, you burn the L-BTC and the federation releases the BTC. The system operates on its own consensus, that of the federation, not Bitcoin's. After all, Bitcoin maintains its integrity and security.

The mechanics of the theft and market reaction

Liquid had about 4,200 BTC locked in the federation's wallet. The attacker exploited a validation flaw in Liquid's software (Elements) and managed to create L-BTC without real backing—in short, out of thin air. This allowed them to withdraw 4,000 BTC, leaving only 200 in reserves. The incident did not touch the Bitcoin network itself, but rather the secondary layer.

Despite this, BTC pricing barely moved: markets know that this is not an attack on the base. Furthermore, the attacker contacted network administrators via on-chain transactions—a detail some interpret as a sign of an "ethical hacker" and others as a simple boast.

Meanwhile, analysts such as Álvaro de María, CEO of BTC Consulting 360, continue to evaluate Bitcoin's path toward $100,000, the impact of ETFs, and institutional capital return. The Liquid incident is a good example of the risks associated with secondary layers, but not a threat to the main network.

In summary, the loss of $320 million is a reminder that additional layers carry their own level of risk. However, while the attacker promises to return the funds, prudence suggests that we shouldn't celebrate until the L-BTC are back. We will update this as more information becomes available.