Angry upvote you horrible genius.

Depends which exchange you're using.

My speculations:

• "insecure from the start" - as in , the wallet was never that "cold"

• with that amount of money, it's easy to imagine an "insider threat"

• the hackers could have gotten lucky and struck right when the company was doing legitimate operations on the wallet

• but probably it's a towering mountain of incompetence, composed of the elements above and more

It's a common misconception that a "cold wallet" is offline. It's still on the blockchain like any other wallet, it's just the keys that aren't on any network-connected computer.

It appears that in this case hackers managed to trick Bybit employees into entering the keys into a fake UI that gave the hackers access to them.

What I don't quite understand is how there is 1.5 billion in a single wallet. Or how are these things structured?

This article puts their total assets under management at $15.7b, which are held in different cryptocurrencies with ethereum at just above $5b.

So I am wondering how they have more than 1/6 of their Ethereum in a single wallet or were these multiple that were connected and got compromised through the same vulnerability? How expensive is it to have more individual wallets? Would it not be feasible to have it split in something like $100m chunks? Or any other more moderate size.

I recommend gloves.

Well, either it wasn't as offline as they all thought, or someone pulled off an epic inside job.

Social engineering, they convinced multiple key holders to sign a transaction.

With steely determination

Even regular banks can be hacked, this isn't just a crypto issue. Same group that hacked byebit also is responsible for the below:

https://en.m.wikipedia.org/wiki/Bangladesh_Bank_robbery

This is the same hacker group that performed the Bangladesh Bank robbery, that attack the almost stole 1 billion, the only reason they got flagged was a typo. They did manage to steal 81 million though. Byebit does seem to have bad security though compared to Bangladesh bank.

https://en.m.wikipedia.org/wiki/Bangladesh_Bank_robbery