Report: Ronin Crypto Hackers Find New Mixer to Convert Stolen ETH to BTC 

The hacking collective believed to be behind the $625-million Ronin bridge hack has transferred stolen ether into bitcoin using a cryptocurrency mixing service the US Treasury has not yet targeted, according to a new report. 

Lazarus Group, initially sanctioned by the Office of Foreign Assets Control (OFAC) in 2019, has used OFAC sanctioned cryptocurrency mixing services Blender.io and Tornado Cash to attempt to move and conceal funds. 

Hackers have more recently tapped ChipMixer, a mixer founded in 2017 that has yet to be added to OFAC’s blocked list, according to the report  from blockchain security firm SlowMist. 

Lazarus Group converted 25.5 million USDC to ETH in March 2022. In the days that followed, hackers moved the ETH to various exchanges, including FTX and Crypto.com before withdrawing to the bitcoin network and mixing it through Blender.io, which the Treasury sanctioned in May. 

Between April and May, the group moved funds through Tornado Cash, which was added to OFAC’s blocked list earlier this month. 

Many of the funds were mixed through various services, the report said. Roughly half of the laundered bitcoins have been run through ChipMixer, according to SlowMist. 

“36.6% of laundered funds are currently held at the hacker’s address, totalling 2,586 BTC,” the report noted. “6.2% of funds laundered were moved to Blender, with 3.8% of laundered funds moved to CryptoMixer and a small percentage to other unknown entities.” 

The report comes as 2022 has seen an uptick in the use of crypto mixing services, which allow users to conceal the transaction history of certain cryptocurrencies by pooling and mixing them together with other users’ funds. 

The 30-day moving average of value received by mixers reached an all-time high of nearly $52 million worth of crypto on April 19, according to a July report by Chainalysis — or roughly double the volumes at the same time in 2021.

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