Japanese cryptocurrency exchange DMM Bitcoin announced on Friday (31st) afternoon that they detected an unauthorized leak of bitcoins in their platform wallet. The amount of illegally leaked bitcoins was 4502.9 BTC, valued at approximately 48.2 billion yen (around 308 million USD).
In the announcement, DMM Bitcoin stated that they are still investigating the details of this loss and have taken measures to prevent unauthorized leaks. To ensure additional security, some trading and withdrawal functions on the platform will be restricted.
DMM Bitcoin also mentioned that all bitcoin deposits of their customers will be fully guaranteed, “as we will obtain funds equivalent to the leaked BTC with the support of the group company.” DMM Bitcoin’s parent company is the Japanese e-commerce group DMM Group.
Data from the blockchain security company Beosin shows that hackers have dispersed the stolen bitcoins from DMM Bitcoin to 10 addresses, and their tracker will continue to monitor the flow of funds. The online intelligence platform Arkham has announced the establishment of a special bounty for this incident to identify the hackers.
Beosin believes that hackers may have used two attack methods. The first is a traditional exchange attack: DMM Bitcoin’s signature service was compromised or the multi-signature private key was leaked, allowing the attacker to use similar historical transfer addresses to receive funds to avoid monitoring and detection. The other potential reason for the hack is that the exchange wallet controller fell victim to address deception, where only the first 5 and last 2 letters of the receiving address were checked during the transfer, leading to funds being mistakenly transferred to the hacker’s address.
Source:
Beosin Alert