Time changes what a key compromise can actually do.

Even if an attacker reconstructs both user keys A and B, the delayed fallback cannot be used until its CSV condition matures.

Before then, the legitimate owner can use (A or B) + C to spend the current vault output V0 into a new output V1.

Once V0 is spent:

• transactions prepared against V0 become invalid
• V1 becomes the active vault output
• the fallback delay starts again on V1

The keys remain A, B and C.

BitVault does not remove the key compromise. It creates a response window in which the legitimate owner can refresh the UTXO before the attacker’s delayed path becomes available.

Read the full analysis:
https://blog.bitvault.sv/if-your-coldcard-was-integrated-with-bitvault/

P2A and ephemeral dust solve different parts of the same operational problem.
P2A defines a compact, keyless anchor output. A wallet, watchtower, service, or other party can spend it without receiving privileged signing material from the parent.

Ephemeral dust policy allows that anchor to have zero value when a zero-fee parent creates it and the package spends it immediately. The child must still add another confirmed input to pay the fee.

Because the anchor is keyless, TRUC and package replacement behavior are the practical anti-pinning layer. P2A supplies the hook. TRUC keeps competition for the hook manageable.

Read: https://blog.bitvault.sv/package-relay-and-ephemeral-anchors-how-bitcoin-transactions-adapt-to-a-changing-fee-market/

Thank you @Simply Bitcoin for having us to speak about how Bitcoin's protocol-level programmability now enables a flexible vault that is resistant to any physical or cyber vulnerability.

BitVault is now live on iOS.

Self-custody security should not depend on one key, one device or one irreversible moment.

BitVault combines multisig coordination, hardware-wallet signing and time-delayed Bitcoin transactions to create a window to detect and react before funds move.

For the official launch:
— 1 year of BitVault Pro + 1 hardware-wallet voucher: $199
— 2 years of BitVault Pro + 2 hardware-wallet vouchers: $299

The 2-year package supports any mix of Keystone 3 Pro BTC-Only and Jade Plus, giving new users the two compatible signing devices required for a complete multivendor setup.

BitVault requires two supported hardware wallets. The 1-year package is best suited to users who already own, or plan to acquire separately, a second compatible device.

Limited launch allocation. Explore the packages and download BitVault for iOS: https://www.bitvault.sv/

A pre-signed Bitcoin transaction can be valid, fully authorized, and still fail to propagate when it is finally needed because its fee was chosen for a market that no longer exists.

Package relay addresses the mismatch by letting a node evaluate a low-fee parent and a fee-paying child together. The parent remains a separate transaction with unchanged signatures and outputs. The child contributes the fee required by current conditions.

This is especially relevant for vaults, Lightning channels, inheritance plans, and any system that signs before broadcast.

The authorization can be fixed early. The confirmation priority can remain flexible.

Read: https://blog.bitvault.sv/package-relay-and-ephemeral-anchors-how-bitcoin-transactions-adapt-to-a-changing-fee-market/

Some days ago our @Riccardo Biffi took the stage at #bcc8333 to talk about our approach to a trustless keys recovery system. Give it a look at www.b-ssl.com. Thanks SatoshiPassion for the awesome pics!

One way to think about it:

Bitcoin removes trusted third parties.
But it also removes "privacy by default".

Everything is transparent unless you actively design against it.

Tools like zpubs are useful.
But they are also dangerous if misunderstood.

This is why security is not just cryptography. It's architecture + behavior + information exposure.

More here → https://blog.bitvault.sv/from-a-zpub-to-your-private-key-the-hidden-risk-most-people-miss/