Recently, 48.2 billion yen worth of bitcoins were leaked from DMM Bitcoin, a Japanese cryptocurrency exchange (CEX), which became a hot topic. At this time, the company has not made any detailed mention of the cause of the unauthorized leak. However, the most likely theory is that there was a gap in the management of private keys, which was the cause. In addition, since last year, the number of hacking incidents due to private key leaks has increased significantly.
In Q1 of this year (January to April), there were 13 private key leak incidents, with a total damage of 460 million dollars (approximately 73.8 billion yen). In addition, of the losses due to Web3.0 hacking in this quarter and throughout last year, the attack method of illegally obtaining private keys accounted for about 60% of the total, making it the largest proportion (※1).
※1: See 2024Q1 Global Web3 Security Report, AML Analysis & Crypto Regulatory Landscape