Hacker Moves Crypto Stolen From Ronin Breach to Help Cover Its Tracks

(Bloomberg) -- A hacker moved some of the roughly $600 million in cryptocurrency stolen from the Axie Infinity play-to-earn gaming platform to a service that helps users mask transactions.  

About 2,000 Ether tokens, valued at around $7 million, that were lifted from Axie Infinity’s Ronin software bridge last month were moved Monday to Tornado Cash, blockchain data shows. Tornado Cash founders did not respond Monday to a request for comment.

Tornado Cash is designed to preserve privacy on the Ethereum blockchain. Its technology breaks the link between the sender and receiver’s addresses on transactions sent to the Ethereum blockchain. The protocol has been used in the past by hackers who took $34 million from Crypto.com. 

“Tracking funds after any mixer, including Tornado Cash, is a probabilistic method and we cannot be 100% certain,” blockchain analysis firm Merkle Science wrote in an email response.

The main Ethereum address used by the hackers who attacked Axie Infinity’s Ronin blockchain sent 2,001 Ether to another Ethereum address earlier Monday. The second Ethereum address then sent 2,000 Ether in batches of 100 Ether each to Tornado Cash, blockchain data shows. The transactions were confirmed by blockchain data firm Nansen.

Ronin is a software bridge built to reduce the traffic and cost on the Ethereum blockchain caused by the popular game Axie Infinity. The bridging technology has been under fire after more than $1 billion worth of cryptocurrencies were stolen in a little more than a year from crypto bridges. 

Sky Mavis, the company behind Ronin and Axie Infinity, said “the investigation is ongoing and we aren’t commenting at this time.”

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