Bitcoin Core Developers Discover Critical Wallet Migration Bug in Versions 30.0 and 30.1 – What You Need to Know

• What’s the Critical Bug in Bitcoin Core?
• How Does the Bug Trigger?
• When Will the Fix Be Released?
• How Can Users Check If They’re Affected?
• Community Reaction: Mixed Responses
• What’s Next for Bitcoin Core?
• FAQs

Bitcoin Core developers have identified a critical bug affecting wallet migrations in versions 30.0 and 30.1, which could lead to potential loss of funds if not addressed. The issue arises during the migration of legacy wallets to modern descriptor wallets, particularly when pruning is enabled. While the team has promised a fix in the upcoming 30.2 release, users are advised to avoid migrating wallets until then. This article breaks down the bug, its implications, and how users can safeguard their assets.

What’s the Critical Bug in Bitcoin Core?

Bitcoin CORE developers recently disclosed a severe bug in versions 30.0 and 30.1 that impacts wallet migrations. The issue occurs when users attempt to migrate from legacy (BDB) wallets to modern descriptor wallets. In rare cases, this process can result in the deletion of all wallet files on the same node, potentially leading to irreversible fund losses if backups aren’t available.

How Does the Bug Trigger?

The bug activates under specific conditions:

• When pruning is enabled and the wallet is loaded during the pruning process.
• When migrating a legacy wallet that relies on the deprecated wallet.dat file format (no longer default since Bitcoin Core 0.21).

Developers clarified that the bug only affects migration attempts and doesn’t compromise existing wallets or node operations. However, they’ve removed the affected binaries from bitcoin.org as a precaution.

When Will the Fix Be Released?

The bitcoin Core team has confirmed that version 30.2 will include a patch for this issue. Until then, users are strongly advised to:

• Avoid migrating legacy wallets using versions 30.0 or 30.1.
• Back up their wallet directories to an external medium.
• Refrain from restarting or updating nodes until 30.2 is available.

How Can Users Check If They’re Affected?

Lacie Zhang, a market analyst at BTCC, suggests that technically proficient users can assess their risk by:

• Verifying their Bitcoin Core version.
• Inspecting debug.log for pruning status and migration attempts.
• Checking if their wallet directory uses a custom or mounted path.

“If you haven’t migrated yet, back up everything immediately,” Zhang emphasized. “The risk is highest if pruning is enabled and a migration is pending.”

Community Reaction: Mixed Responses

The disclosure has sparked varied reactions. While the Core team’s transparency has been praised, some Crypto Twitter users have criticized the oversight. The incident follows earlier debates about Bitcoin Core’s v30 release, which faced delays due to disputes over arbitrary data storage capabilities on the blockchain.

What’s Next for Bitcoin Core?

Developers are working diligently to resolve the issue, but the incident underscores the importance of thorough testing—especially for critical functions like wallet migrations. For now, users should stay informed and follow official updates.

FAQs

Is my Bitcoin Core wallet safe?

Yes, existing wallets remain unaffected. The bug only impacts migration attempts from legacy to descriptor wallets.

Should I downgrade to an older version?

No. Downgrading isn’t recommended. Instead, wait for version 30.2 and avoid migrations until then.

Can I still use Bitcoin Core normally?

Absolutely. The bug doesn’t affect regular wallet usage or node operations.