Nearly all of the $600 million stolen from cryptocurrency Poly Network has now been returned by hackers, according to the platform targeted in the hack.
Poly Network said that all of the funds except $33 million worth of the tether digital coin have been transferred back.
Shortly after the hack the anonymous individual posted notes to the publicly available blockchain taunting the company and asking for advice on how to launder his stolen riches.
Later, the criminal claimed “not to be interested in money” and promised to return it all.
Poly Network appears to have accepted the explanation and dubbed the hacker “Mr White Hat”.
White hat hackers are ethical security researchers who use their skills for good to help organisations find security flaws.
Poly Network requested they send the money to three digital currency wallets and the hacker then returned more than $342 million of the funds to those wallets by 12 August.
The attack is one of the largest hacking heists in history. Poly Network said the person had exploited a vulnerability in its system.
However, while almost all of the haul has been sent back to Poly Network, the last $268 million of assets is locked in an account that requires passwords from Poly Network and the hacker to gain access.
Poly Network is what’s known as a “decentralized finance” (DeFI) system. DeFi projects aim to use blockchain — the technology which underpins most cryptocurrencies — to replicate traditional financial services like loans and trading.
In Poly Network’s case, the DeFi system allows users to transfer tokens from one blockchain to another.