Binance’s $6.3 billion theft raises custody concerns as Bitcoin network remains unhacked

A $6.3 billion theft from Binance has renewed scrutiny of cryptocurrency custody, highlighting the distinction between an exchange security breach and an attack on the Bitcoin network. The incident also exposed the risks of concentrating assets with a single custodian.

In her November 2 broadcast, Natalie Brunell discussed Binance’s response and stressed that “Bitcoin, the network itself was not hacked.” She said the incident showed that even large institutions could have vulnerabilities customers could not see.

Brunell said the FBI had attributed the attack to a North Korean hacking operation. Most of the stolen funds disappeared within 20 minutes. According to her account of Binance’s findings, the attack may have begun with an engineer’s laptop and compromised withdrawal authorization systems, allowing the exchange’s infrastructure to approve the transfers. Binance reported no evidence that private keys had been stolen, while investigators uncovered several additional security breaches.

Binance promised to cover all customer losses through its emergency fund and corporate reserves and said it had already replaced 95% of the stolen assets with its own money, Brunell reported. Roughly $3 billion was frozen, largely through Tether and Circle freezing stablecoins. Customers nevertheless withdrew a net $4.7 billion after some withdrawals resumed, equivalent to nearly 3% of Binance’s assets. The exchange said those outflows were stabilizing.

Brunell highlighted the danger of keeping all assets in one place and discussed multisignature Bitcoin custody, which requires approval from multiple keys and can reduce dependence on any single key. She also said AI was making some cyberattacks cheaper and easier to execute, adding to the importance of custody security.

Turning to corporate Bitcoin holdings, Brunell said Strategy reported a record quarterly operating profit of nearly $21 billion, more than five times the year-earlier figure. Most of the profit reflected appreciation in its Bitcoin holdings rather than its software business, as new accounting rules recognize those gains in income even without a sale.

Strategy held approximately $4.9 billion in cash and reserves, enough to meet more than three years of dividend and interest obligations, she said. The company also disclosed the purchase of another 811 Bitcoin for around $65 million, taking its holdings above 849,000 Bitcoin. Brunell described its approach as using Bitcoin as a foundation for new financial products.

Brunell then discussed Bitwise’s long-term scenario analysis, which considered Bitcoin’s potential share of the market for assets used to preserve wealth, including gold. Her account outlined bullish, base and bearish scenarios built around different assumptions about adoption.

She stressed that those scenarios were projections rather than guaranteed outcomes. Discussing her interview with Lynn Alden, Brunell said weaker adoption or a substantially different financial environment could undermine expectations. Her discussion paired those conditional assumptions with the custody risks exposed by the Binance breach.