Japanese Exchange DMM Suffers $305M Bitcoin Loss in Private Key Hack

Key takeaways:

• After its systems were hacked on May 30, the centralized crypto exchange DMM lost over $305 million in Bitcoin.
• DMM afterward acknowledged on its website that it had lost precisely 4,502 BTC in an attack, suggesting that it was probably the reason behind that specific transaction.

After its systems were hacked on May 30, the centralized crypto exchange DMM lost over $305 million in Bitcoin. Every user deposit “will be fully guaranteed,” the exchange promised, confirming the hack on its website.

Withdrawals, new account openings, spot purchase orders, and all leveraged orders have been temporarily suspended by the exchange. Limit orders, however, cannot be canceled after they have been placed.

When analytics site Whale Alert reported the following on May 30, at 10:14 p.m. UTC, crypto users started talking about the attack on social networking platform X:

“4,502 #BTC (308,948,771 USD) transferred from unknown wallet to unknown new wallet.” 

The post included a link to blockchain data demonstrating an outflow of 4,502.9 BTC from a single wallet, or $305 million at today’s exchange rates.

The owner of the wallet was identified as “unknown” by Whale Alert. On the other hand, DMM afterward acknowledged on its website that it had lost precisely 4,502 BTC in an attack, suggesting that it was probably the reason behind that specific transaction.

According to the exchange, steps have already been taken to stop the “unauthorized leak.” It will obtain the corresponding quantity of Bitcoin to guarantee payment to each and every user. The acquisition of these funds will be facilitated by “our group companies.”

When all services are restored, a fresh alert will be released, therefore, users are advised to keep a watch out for notices, the team said.

The e-commerce firm DMM Group is the owner of DMM Exchange. January 2018 saw its launch. A crypto mining company is also owned by the company.

Crypto exchange users continue to face issues with fraud and hacks. In November, an attacker took possession of the Poloniex exchange’s private key, causing the exchange to lose more than $100 million. A comparable attack against GDAC in April 2023 cost the company $14 million.