The Bitcoin Core Project has issued a warning regarding a wallet migration vulnerability in Bitcoin Core versions 30.0 and 30.1. In rare cases, migrating older BDB wallets using these versions may result in the deletion of all wallet files on the same node, potentially leading to loss of funds if backups are not available. The project advises against using these versions for wallet migration until a fix is released with Bitcoin Core 30.2. Other functionalities, including node operations and existing wallet usage, remain unaffected.