AscendEX disclosed multichain hot-wallet breach as losses were estimated at $77.7 million

AscendEX disclosed on December 12, 2021, that unauthorized transfers had left one of its internet-connected hot wallets, prompting the cryptocurrency exchange to suspend deposits and withdrawals while it investigated. Blockchain security firm PeckShield estimated that assets worth approximately $77.7 million had moved across Ethereum, Binance Smart Chain and Polygon.

The incident mattered beyond its immediate dollar value. AscendEX was a centralized custodian holding many different tokens across several networks, so the breach illustrated how one compromised operational system could expose assets that otherwise belonged to unrelated protocols and communities. It also placed the exchange’s reimbursement promise, balance sheet and wallet controls under scrutiny.

What AscendEX disclosed

In its initial December 12 statement, AscendEX said it had detected transfers of ERC-20, Binance Smart Chain and Polygon tokens from a hot wallet. It said its cold wallets were not affected and promised that any customer funds affected by the incident would be covered completely. Those were contemporaneous company representations; the surviving public record available that day did not independently establish the size of the exchange’s cold-wallet reserves or its capacity to make every customer whole.

During a company-hosted discussion at 16:00 UTC on December 12, executives said the unauthorized activity had been identified late on December 11. They expanded the reported network scope to include Litecoin and Bitcoin Cash, in addition to Ethereum-based tokens, Polygon and Binance Smart Chain. AscendEX said unaffected assets had been moved into cold storage and that it was working with blockchain-forensics firms, other exchanges and law enforcement.

The exchange also said deposits and withdrawals would return only after new hot-wallet infrastructure had been reviewed. Trading availability did not remove the central custody constraint: customers could not freely move assets off the platform while those services remained suspended.

Understanding the $77.7 million estimate

PeckShield’s December 12 estimate divided the identified value into approximately $60 million on Ethereum, $9.2 million on Binance Smart Chain and $8.5 million on Polygon. Those three figures sum to $77.7 million.

That total was an external estimate, not an audited loss figure from AscendEX. PeckShield’s public post did not provide a complete valuation methodology, pricing venue or precise price timestamp for every token. Crypto assets trade continuously, some of the transferred tokens had limited liquidity, and converting large balances into dollars at quoted prices could overstate realizable proceeds. The estimate also did not expressly include the Litecoin and Bitcoin Cash transfers mentioned later in AscendEX’s December 12 discussion.

Public Ethereum records independently show outbound activity from an address labeled by Etherscan as an AscendEX hot wallet, including a 40 ETH transfer at 23:21:14 UTC on December 11 to an address later labeled “AscendEX Hacker.” Address labels are maintained by the explorer and can be revised; that transaction corroborates activity on Ethereum but cannot, by itself, prove the ownership, cause or total value of the broader incident.

What remained unresolved on December 12

AscendEX had not published a technical postmortem by the end of December 12. The entry path, private-key exposure, complete asset inventory and final loss were therefore unknown. Its statements about unaffected cold wallets, cooperation with the FBI and full reimbursement remained company claims or commitments rather than independently verified outcomes.

The event-day conclusion is consequently narrow: AscendEX confirmed unauthorized hot-wallet transfers, halted deposits and withdrawals, and promised customer reimbursement; PeckShield supplied the contemporaneous $77.7 million estimate. Any later account of the root cause, recovery or compensation belongs to a subsequent record and should not be projected backward into the information available on December 12, 2021.