According to the blockchain analytics firm Elliptic, BTC stolen from KuCoin during the September 25th KuCoin hack is being laundered through ChipMixer.
“The KuCoin thief has now started to move the stolen BTC,” said Elliptic chief scientist and co-founder Tom Robinson. “The process is ongoing, but of the 1,008 BTC stolen, 425 BTC have now been sent to ChipMixer, a mixing service. This started on Monday morning.”
What is ChipMixer?
“ChipMixer creates BTC addresses and funds them with specific sizes. These are chips with 0.001 BTC, 0.002 BTC, 0.004 BTC, and so on till 8.192 BTC. When you deposit your BTC, you receive the same amount in chips. For example you deposit 0.112 BTC and you receive 0.064 + 0.032 + 0.016 chips. Each chip was funded before your deposit, so there is no link between them and your deposit on the blockchain. They are already anonymous…Since you can use split/merge, nobody knows if you’ve withdrawn big or small chips. It is not required to use, but the existence of this option increases your privacy,” says the ChipMixer website.
In other words, ChipMixer is a tool that criminals use to obfuscate their paper trails so that they can commit crimes while leaving no evidence behind. Unfortunately–but not surprisingly–BTC mixing service-usage has been on the rise. According to a report released in May by Crystal Blockchain, the cryptocurrency analytic and transaction tracing platform created by Bitfury, there has been an increase in darknet transaction flows between BTC mixing services.
The September 25 KuCoin hack
KuCoin, the Singapore-based digital currency exchange, was hacked for $274.1 million on September 25th. By October 3rd, KuCoin had allegedly identified the hacker and recovered $64 million worth of stolen funds, however, the remaining $210 million remains at large.
Tens of millions of those funds were laundered through the decentralized exchange UniSwap, and now, roughly $5.8 million of those funds have been laundered through a BTC mixer.