BITCOIN CORE MERGES A WALLET ENCRYPTION FIX — A FAILED DATABASE WRITE COULD “LEAVE PLAINTEXT KEYS ON DISK” — NOT IN A RELEASE YET

Bitcoin Core merged a fix on September 22, 2026 for how its wallet handles encryption. It is pull request #35752, written by developer l0rinc and merged by maintainer Ava Chow. Bitcoin Optech listed it in its October 2 newsletter. The pull request puts the problem plainly: "erase failures can leave plaintext keys on disk."

The bug lives in the moment you encrypt a wallet or change its passphrase. If a database write failed partway through, the pull request says, "Encryption can report success without persisting the master key," and "a re-encryption failure during a passphrase change can leave a previously locked wallet unlocked." The screen says encrypted. The file may not agree.

The fix only marks the wallet as encrypted after the database write actually lands, so a failure leaves the keys as they were and the step can be tried again. It is merged into the main branch, not shipped. The newest release on bitcoincore.org is 31.1, and the pull request carries no backport label.

Your keys are only as safe as the file they sit in. It takes a failed write to trigger this, which is rare, but a wallet that says encrypted should be encrypted. If you encrypted a Bitcoin Core wallet or changed its passphrase, check that it still asks for the passphrase before it signs, and keep your backup. At the time of this writing, bitcoin was $84,892.