Binance Bridge has suffered a massive cyber-attack that resulted in the seizure by threat actors of 2 million Binance Coins (BNB) worth $566 Million.
The attack was launched at 14:30 on October 6, 2022, and the threat actors transferred the seized funds to their wallets through two transactions of 1,000,000 BNB each. Detecting the security breach at 18:19, Binance paused BNB Smartchain transactions.
In the statements made by Binance officials on social media, the attack was confirmed, and it was announced that the security weakness that caused the attack was under control. It was also stated that a large part of the seized funds remained and secured on BNB Smartchain.
As a result of the attack, it is predicted that $70 Million to $80 Million worth of crypto money was withdrawn from Binance BNB Smartchain by threat actors. Suspended BNC Smartchain transactions have been resumed as of October 7, 2022. Investigations are regarding the violation continue.
What did BNB Chain say about the exploit?
BNB Chain published an official update dated 7 October 2022. It says the target was BSC Token Hub, the native cross-chain bridge between BNB Beacon Chain (BEP2) and BNB Smart Chain (BEP20). In total, 2 million BNB was withdrawn, and the team said the vast majority of the funds remained under its control. It described the method as a sophisticated forging of a low-level proof in one common library.
The team contacted community validators one by one to stop the incident from spreading. At that time BSC had 26 active validators out of 44 in total. The chain was suspended, and the team apologized for that and said “We own this.”
What did BNB Chain propose afterward?
The same update lists proposals for on-chain governance votes: whether to freeze the hacked funds, whether to use BNB Auto-Burn to cover remaining losses, a whitehat program paying $1M per significant bug, and a bounty of up to 10% of recovered funds for catching the attackers. The team also promised a validator voting feature through a Beacon Chain upgrade, a postmortem, a new on-chain governance mechanism and more community validators. The update does not name the attacker, and it was written before the votes took place.
Why do cross-chain bridges attract attackers?
A bridge holds or mints assets on one chain against deposits on another. It relies on proofs that one chain checks about events on the other. If an attacker can forge such a proof, the bridge may release funds that were never deposited. That is why a single flaw in proof checking can reach a very large sum, as the 2 million BNB shows.
For users and exchanges, the case shows that a bridge is only as safe as its verification code. Check an official channel for status before moving funds during an incident, and treat unsolicited links claiming to offer refunds with suspicion. Our vulnerability management and patch management pages explain how teams track and fix flaws like this one.