Proponents are trying to build networks that allow users to buy and sell digital assets directly with each other, bypassing intermediaries that might impose fees, such as an exchange or clearing house. Many projects aim to be fully decentralised.
The alleged hacker exploited a vulnerability in Poly Network's "contract calls", a type of test that is not intended to be published on the blockchain, to access the ledgers and transfer money out, the network said.
The tokens were valued at about US$600m prior to the news of the alleged hack, consisting of more than US$270m on the ethereum blockchain, US$250m on the Binance Smart Chain and US$84m on the Polygon network, according to wallet addresses published by Poly Network on Twitter.
Etherscan indicated that the hacker had taken alt-coins such as Binance Coin and Ether, as well as dozens of smaller tokens, including Shiba Inu, Matic and Uniswap. The dollar value of the stolen coins dropped to US$394m as news of it spread and investors sold some cryptocurrencies, knocking the tokens' prices.
Poly Network called on groups known as "miners" — which process transactions — and centralised crypto exchanges to help block transfers. "We will take legal actions and we urge the hackers to return the assets," it said.
Changpeng Zhao, chief executive of Binance, said his company was aware of the incident. He said while "no one controls" Binance's blockchain, the group was "co-ordinating with all our security partners to proactively help. There are no guarantees. We will do as much as we can."
Paolo Ardoino, chief technical officer at stablecoin company Tether, said the group had frozen about US$33m worth of its tokens, which were on the Poly Network. A substantial proportion was also in USD Coin, operated by payments service company Circle, according to Etherscan. Circle did not immediately respond to a request for comment.
Earlier this month Gary Gensler, chair of the Securities and Exchange Commission, the US markets regulator, called on lawmakers to give watchdogs more powers to protect investors from illicit activity on DeFi platforms.
Written by: Siddharth Venkataramakrishnan and Philip Stafford
© Financial Times