Bitcoin Core V30 Bug Risks Fund Loss During Legacy Wallet Upgrades
Bitcoin Core urged users of versions 30.0 and 30.1 not to migrate legacy wallets after discovering a bug that can delete all files in a wallet directory if migration fails.
Bitcoin Core developers warned users on Monday of a wallet migration bug in versions 30.0 and 30.1 that can delete files and result in fund loss.
The issue occurs under specific conditions and affects migrations from old Bitcoin Core wallets that were never renamed or upgraded.
Lacie Zhang, market analyst at Bitget Wallet, told Cointelegraph that the bug is triggered when the software attempts to migrate an unnamed legacy “wallet.dat” file stored in a custom wallet directory, often defined using “-walletdir” setting, while pruning is enabled.
In these cases, the migration can appear to complete successfully, but the cleanup logic mistakenly deletes the entire wallet directory, and if a user does not have an external backup, “loss of access to funds is effectively guaranteed because all local wallet files are removed.”
Shawn Odonaghue, community lead at layer-3 blockchain Orbs, told Cointelegraph that the bug primarily impacts “very old wallet setups,” and that users with a hardware wallet or modern wallet software are unlikely to experience such issues.
Related: Bitcoin Core wins rare praise as independent audit finds no serious flaws
Bitcoin Core 30.1 was released on Jan. 1 and the wallet migration bug was publicly disclosed on Monday, with developers pulling the 30.0 and 30.1 binaries from the official download site.
The project told users not to use the wallet‑migration tools until a fixed release, Bitcoin Core 30.2, is available, stressing that existing users who are not attempting migrations can continue running their nodes as normal.
Zhang added that technically proficient users can assess their exposure by checking whether they are running Bitcoin Core v30.0 or v30.1, determining whether their wallet is a legacy wallet, inspecting “debug.log” to see whether pruning is enabled and whether any migration attempts have already occurred, and by reviewing the directory layout to confirm whether “-walletdir” points to a custom or mounted location.
Source: CoinTelegraph
