BNB Chain Halted After Estimated $100 Million Drain in Exploit, CEO Says Issue Has Been Contained

Transactions on the Binance blockchain, also known as BNB Chain and Binance Smart Chain, were halted today after a potential exploit in the network was detected through a spike in “irregular activity.” Changpeng Zhao, Binance's chief executive, said on Twitter that the issue involved BSC Token Hub, a so-called cross-chain bridge. These enable the transfer of digital assets and information from one independent blockchain to another. “The issue is contained now. Your funds are safe,” Zhao wrote, apologising for the inconvenience.

The BSC Token Hub is used to facilitate cross-chain transactions between BNB Beacon Chain and Binance Smart Chain. As such, the exploit resulted in the loss of extra Binance Coins (BNB). However, all validators on the network have been asked to suspend the Binance smart chain. Although users remain worried about their funds, CZ maintained that all funds were safe and that the public will be updated with more details going forward.

Two hours before Zhao's tweet, the official Binance Twitter account wrote that BNB Chain was under maintenance and apologised for the inconvenience. “We will suspend all deposits and withdrawals via BNB Chain temporarily until there are further updates,” Binance wrote.

Additionally, Binance confirmed on Reddit that around $100 million (roughly Rs. 823.5 crore) to $110 million (roughly Rs. 906 crore) worth of funds had initially been moved from the BNB Chain. However, after alarming feedback from security officials and community members, Binance confirmed that funds worth $7 million (roughly Rs. 57.6 crore) have been frozen.

According to blockchain security firm SlowMist, the exploit allowed cybercriminals to get away with over $570 million (roughly Rs. 4694.5 crore) in digital assets, including Ether, Polygon, BNB Coin, Avalanche, Fantom, Arbitrum, and Optimism. “The attacker is spewing funds across liquidity pools and utilizing every bridge they can to get to safer chains,” blockchain developer @0xfoobar tweeted, adding that there was “complete chaos on the chain.”

The final total value involved in the hack has yet to be determined.