Arbitrum Council Moves $30M in Binance Hack Funds

Arbitrum’s Security Council moved 8,425 ETH and 74,559,805.2 ARB linked to the Binance exploit into a frozen address on Oct. 30, according to the council’s emergency notice. CoinDesk valued the assets at about $30 million; they can no longer be moved by the address associated with the exploit.

How did the council move funds without the hacker’s key?

The council temporarily changed Arbitrum’s Inbox contract, which carries messages from Ethereum to Arbitrum, to add a function that could send transactions as if they came from the exploiter’s address. It used that function to transfer the assets, then restored the original contract implementation in the same atomic action, the notice said.

CoinDesk reported that the 12-member council has emergency upgrade powers requiring approval from nine members. The operation used those powers to move the tokens without a signature from the address’s private key.

Where are the assets now?

The assets are held at an address ending in 0DA0, the council said. Its notice said no other users’ funds or applications were affected and that only an ArbitrumDAO governance vote can move the assets from the holding address.

Binance said the broader incident affected about $6.34 billion in digital assets in an update published Nov. 3. The council’s notice did not give a value for the Arbitrum assets or say when a governance vote would take place.

What has to happen before the funds can move again?

An ArbitrumDAO governance vote is required to release the frozen assets, with the process to be coordinated with relevant parties, according to the council. No vote date or timetable was announced in its Oct. 30 notice.

References

• the council’s emergency notice — forum.arbitrum.foundation