BNB Token Hub: a bridge accepts a proof that should not exist

On 6 October 2022, an attacker obtained two million BNB through the BSC Token Hub bridge. Their value at the time exceeded half a billion dollars. This is a different incident from the Binance hack of October 2026: here, the flaw affects a mechanism linking two chains.

The bridge must verify that an event on one network allows one operation on the other. The attacker exploits a verification flaw to get false proof of messages accepted. Additional BNBs can thus be unlocked or created in the bridge circuit without corresponding legitimate consideration.

Abnormal movements lead to the mobilization of the ecosystem. The validators coordinate a suspension of BNB Smart Chain to limit further operation. Interruption does not magically delete operations that have already been executed or assets that have already passed over other networks.

The balance sheet must therefore distinguish the value of the two million BNB concerned and the sums taken out of the chain. BNB Chain values assets taken out of its network in the range of about $100 million to $110 million; some of it is frozen thanks to partners.

The teams correct the device and the network restarts. The public identity of the author is not established in the selected sources. The power to coordinate a rapid shutdown also becomes a topic of debate on the governance and decentralization of the network.

The technical lesson is concrete: a digital safe can remain intact while the counter that accepts the proof of withdrawal is convinced by a false document.