Odaily Planet Daily reports: Bitcoin wallet service Nunchuk has released a major update, advising users of multisignature wallets containing keys generated by Coldcard to migrate their funds as soon as possible in response to recent Coldcard-related security incidents.
Nunchuk has defined different response levels based on the number of Coldcard-generated keys in the multisig wallet: If the number of Coldcard-generated keys meets or exceeds the signature threshold, an attacker could theoretically transfer funds directly—users in this situation should migrate immediately. If the wallet contains only one Coldcard-generated key and that number is below the signature threshold, a single compromised key cannot move funds on its own, posing a relatively lower risk; however, migration is still recommended as soon as possible. If users are unable to confirm the exact number of Coldcard keys in their wallet, they should treat the situation as high risk.
In addition, Nunchuk has announced that its upcoming mobile update will automatically enable Slipstream channels for paid users. At that time, any transaction from a multisig wallet containing at least one Coldcard key will bypass the public mempool and be submitted via Slipstream to reduce the risk of transaction monitoring and replacement. For users who wish to act immediately or for free users, Nunchuk provides a manual migration option: users must create a migration transaction, complete the multisignature signing but do not broadcast it, then submit the raw transaction data to the Slipstream platform.