Multi-chain interoperability protocol Poly Network fell victim to an exploit today, resulting in the loss of roughly $600 million worth of various cryptocurrencies, the platform's developers revealed.

"We are sorry to announce that #PolyNetwork was attacked on @BinanceChain @ethereum and @0xPolygon," the developers also stated in Poly Network's Telegram channel. "We call on miners of affected blockchain and crypto exchanges to blacklist tokens coming from the above addresses."

According to the announcement, there are currently three known addresses that allegedly belong to attackers: Ethereum (which currently holds $264.8 million worth of crypto), Binance Smart Chain ($250.8 million), and Polygon ($85 million).

As such, this is the largest cryptocurrency hack so far. The previous record was held by exchange Coincheck which lost about $530 million to hackers in January 2018.

What's more, because Poly Network is an interoperability protocol, there may well be other projects that use Poly Network that are also affected. The protocol's website features dozens of other crypto projects with which it is integrated.

Projects halt operations

Shortly after the hack, Poly Network-based cross-chain pool O3 Swap, which allows users to trade tokens between different blockchains, suspended its cross-chain functionality.

“O3 Swap cross-chain function is currently suspended due to the PolyNetwork [hack]. We are in contact with the team. Please be patient to back to full functionality. The non-cross-chain function is available and can be used normally,” O3 tweeted.

In its turn, Tether, the company behind USDT, froze $33 million worth of its stablecoins stolen by the hacker, according to its chief technology officer Paolo Ardoino.

It’s about sending a message

Meanwhile, the crypto community’s eyes remain firmly glued to the hacker.

One pseudonymous crypto enthusiast, called “hanashiro.eth,” even received 13.37 Ethereum (worth about $42,000 at current prices) from the hacker for tipping him off

“DONT USE YOUR USDT TOKEN YOU VE GOT BLACKLISTED,” hanashiro.eth wrote in a message attached to an Ethereum transaction.

Seeing such generosity, other users began bombarding the hacker with messages as well.

One of them claimed to be a refugee from Lebanon when asking the attacker for money. Another just said “Congratz.”