Up to $23.5 million in cryptocurrency lost in Bancor Network hack
The network froze funds to minimise the damage, which is a whole new problem.
At about midnight UTC on 9 July, the Bancor Network was hacked, and attackers made off with about 25,000 ETH (Ethereum) worth around US$12.5 million, 230 million NPXS (Pundi X) worth around $1 million and 3.2 million (BNT) Bancor worth around $10 million.
A wallet that was being used to upgrade some smart contracts was compromised, which is how the attackers got in.
"From the fact that Bancor claims a wallet was hacked and then was able to steal from a smart contract [suggests that the attack] exploits a weakness that has always existed with their smart contracts," says Yo Kwon, CEO and founder of the Hosho cybersecurity firm. "That weakness is how far-reaching a single wallet has been allowed to be. Their smart contracts allow for nearly unlimited control to the owners and apparently their ability to protect their wallets is inadequate."
"Any large source of funds or access to powerful smart contracts should at the minimum be using multi-signature verification."
After the attack, the Bancor network went down and halted trading as a precaution. The stolen BNT was frozen, but the NPXS and ETH can't be frozen. Instead, Bancor is "working together with dozens of cryptocurrency exchanges" to make it more difficult for the hackers to liquidate the funds.
No user wallets were affected, and no funds were stolen except from the Bancor Network itself.
Shortly before the attack, Bancor voiced its support for "decentralised solutions such as Bancor" on Twitter.
That Tweet didn't age well. Firstly the Bancor network went down, which is the number one thing no decentralised system should ever do. On top of that, the central Bancor authority used its executive powers to freeze the stolen BNT, and then appealed to centralised exchanges for help preventing the other funds from disappearing.
The whole point of decentralised solutions "such as Bancor" is that they can never go down, are much better protected against hackers and that no central authority has the ability to do things like freeze funds. Regardless of how the hack may have happened, or whether the ability to freeze funds at will turned out to be advantageous in this case, the point remains that Bancor is not actually decentralised.
Talk is cheap, but walking the hard road to decentralisation is an entirely different level of commitment.
The road to decentralisation is extraordinarily expensive and difficult. It means deliberately building systems to prevent being able to freeze or recover funds like this, and means simply letting go of endless hundreds of millions of dollars worth of tokens over the years, lost to hidden vulnerabilities and coding errors, random bugs and hack attacks like this.
It's pretty steep, but that's just the price of admission and any protocol that's not willing to pay it will never be truly decentralised.
Disclosure: At the time of writing the author holds ETH, IOTA, ICX, VET, XLM, BTC, NANO