The U.S. government says the recent $600 million Ronin Validator cryptocurrency heist was conducted by Lazarus Group, the notorious hacking outfit linked to the North Korean government.
The attribution was contained in a notice from the U.S. Treasury that announced sanctions against the Ethereum address that received the stolen funds.
The mega-million dollar heist is considered the second largest crypto theft of all time and included the siphoning of 173,600 Ether (ETH) and 25.5 million USD Coins stolen from the Ronin cross-chain bridge.
According to data from cryptocurrency security firm Elliptic, the total value of the stolen crypto-assets at the time of the theft was $540 million.
[ READ: Hackers Steal Over $600M in Major Crypto Heist ]
The company said it has seen evidence the North Korean hacking group has already managed to launder about 20% of the stolen digital currency through multiple exchanges.
The quick decision by the U.S. Treasury Department adding the ETH address to the sanctions list effectively means that U.S. entities cannot conduct any transactions with the address.
Late last month, Ronin Network confirmed the security breach that hit the digital ledger used by players of the popular online game Axie Infinity.
North Korean hacking groups have been actively targeting cryptobanks and cryptocurrency exchanges with malware attacks with the Lazarus team conducting APT attacks since at least 2017.
The hacking teams in North Korea have also been seen targeting offensive security researchers and using a fake pen-test company in attacks that employ rich social engineering tactics. The APT group has also been caught sharing zero-day exploits for modern web browsers.
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