Bitcoin Core developers have issued a critical warning regarding versions 30.0 and 30.1 of the software, which contain a bug that risks the deletion of wallet files during migration. The issue specifically affects the process of migrating legacy Berkeley DB (BDB) wallets to modern descriptor wallets. Under rare circumstances, such as when pruning is enabled and a wallet is unloaded during the process, a migration failure can lead to the deletion of all wallet files on the same node, potentially resulting in permanent loss of funds if backups are not available.
The developers have removed the binaries for the affected releases from bitcoincore.org and urge users to avoid migrating legacy wallets using v30.0 or v30.1 until a fix is deployed. A patch is planned for the upcoming Bitcoin Core v30.2 update. The team emphasized that the bug only impacts the legacy wallet migration process; users can continue to run nodes and use existing wallets normally.
Market analyst Lacie Zhang from Bitget Wallet advised technically proficient users to check their Bitcoin Core version, inspect their debug.log for pruning status and migration attempts, and review their directory layout to assess risk. She recommended that users who have not yet migrated should immediately back up their entire data directory and avoid restarting or upgrading until moving to version 30.2 or later.
The bug's discovery has sparked significant concern within the community, with some developers, like Luke Dashjr, expressing grave warnings about potential risks. The release of v30 was already contentious, having been delayed for weeks due to developer disagreements over data storage policies, adding to the frustration surrounding this critical software flaw.
