Bybit Hacked: Over $1.4 Billion In Stolen From Exchange’s Cold Wallet

Singapore-based crypto exchange Bybit has reportedly been hacked, with over $1 billion in Ethereum and other tokens stolen, according to initial estimates.

Bybit CEO Ben Zhou confirmed the incident on X, explaining that hackers exploited a vulnerability in the exchange’s ETH cold wallet multisig system. Zhou stated that signers were tricked into approving a malicious transaction that altered the smart contract logic, allowing the attacker to take control of the wallet and drain its assets.

“The transaction was ‘musked’—all the signers saw the correct address, and the URL was from Safe, but the signing message was to change the smart contract logic of our ETH cold wallet,” Zhou wrote.

Security researchers believe “musked” refers to a manipulated UI that masked the true destination of the transaction, deceiving Bybit’s team into signing off on the fraudulent transfer.

The hacker initially moved the stolen funds—including 400,000 ETH (~$1.1 billion), 90,000 stETH, 15,000 cmETH, and 8,000 cETH—to an address starting with 0x476. They then split the funds across dozens of wallets and began swapping assets on decentralized exchanges like Uniswap, Paraswap, and KyberSwap.

Despite the scale of the attack, Bybit insists that user funds remain safe.

“Bybit is solvent even if this hack loss is not recovered. All client assets are 1:1 backed, we can cover the loss. Withdrawals remain normal,” Zhou assured.

However, BitMEX Research estimates that around 75% of Bybit’s ETH deposits were drained in the attack.

The timing of the breach has raised concerns, as it coincided with scheduled maintenance on Bybit’s live server. The exchange had announced downtime earlier on Tuesday, leading some security experts to question whether the maintenance was linked to the breach.

Bybit has yet to disclose whether law enforcement or blockchain security firms are involved in the investigation. This is a developing story, and further updates are expected as more details emerge.