How to Store a Seed Phrase Safely: What Steel, a Passphrase and Multisig Do for Your Wallet Backup

Seed phrase storage: the weak point that decides who keeps your coins The attack on Coldcard devices, running since the end of July, has steered the debate towards manufacturers, firmware and supply chains. Where a wallet backup actually sits, and in what condition, has barely come up. For most retail investors, that is the more practical question. Coinkite, the manufacturer, set out the issue itself in its security advisory of July 30, 2026: funds from affected seeds are at risk unless the seed rests on at least fifty independent dice rolls thrown in private. That is a statement about how a seed comes into being, not about how it is stored. It leads to the same place all the same. A seed is a piece of information whose value depends entirely on who knows it. The scale of the damage remains open; estimates in the first days of August ranged between $86 million and more than $130 million, depending on the survey and the cut-off date. We described the case and the manufacturer question in our assessment of the Coldcard attack. This article deals with the other half of the problem: how to store those twelve or twenty-four words so that they survive a house fire, a burglary, a house mo...