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A comment on Open-Sourcing Subzero: Square’s Bitcoin Cold Storage Solution. Parent comment

Re:Open-Sourcing Subzero: Square’s Bitcoin Cold Storage Solu... by sneak on Tuesday October 23, 2018 @05:07AM (#18281874)
Moving funds from multisig cold storage is not “freely” when it at the minimum requires two people to travel to two different key storage/signing locations. You’re generally looking at a 12-48h process at a minimum.

“Cold” refers to it being entirely offline.

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Re:Open-Sourcing Subzero: Square’s Bitcoin Cold Storage Solu... by londons_explore on Tuesday October 23, 2018 @08:30AM (#18282760)
In this case, the people are really just part of the system.

If an attacker can fool the people into getting funds out of the cold wallet, then they are available for an attacker to steal.

The only way to avoid the people being fooled is to have full auditing of every customer account balance. One needs to ensure that hot wallet + cold wallet >= all customers account balances.

Doing that auditing in a secure way is really hard.

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Re:Open-Sourcing Subzero: Square’s Bitcoin Cold Storage Solu... by qmarchi on Tuesday October 23, 2018 @11:01AM (#18283931)
Square tried to minimize the impact that a human can have on the system:

* Several people would have to be compromised * The people are geographically diverse * Subzero will refuse to redirect funds to anything but a Square hotwallet. * And, they specifically built the Beancounter system for auditing of these accounts.

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Re:Open-Sourcing Subzero: Square’s Bitcoin Cold Storage Solu... by dwild on Wednesday October 24, 2018 @10:21AM (#18292631)
> If an attacker can fool the people into getting funds out of the cold wallet, then they are available for an attacker to steal.

Sure but then you still have 12-48h to discover that they are being fooled.

There's no foolproof method, there will always be people involved and anything you could make will only make it better because it give you more people/time to realize the mistake. They decided that 2 persons and 12-48h is enough and I agree with that.

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