Bitcoin Core 32 Enters Final Testing with Faster Validation, Fee Changes and Security Fixes

Bitcoin Core 32.0 entered its final testing phase on September 14, with a stable release planned for October 10. The update introduces a new fee estimator, parallel block processing, default use of PSBT version 2 for certain wallet commands, and several security patches.

Improved fee estimation

The software adds a second fee estimator that looks at transactions waiting in the mempool, alongside the existing estimator that examines fees from recent blocks. By comparing both, the node can suggest a lower fee when network congestion eases, allowing fee estimates to drop more quickly after periods of high demand.

Faster block processing

Node validation now uses multiple threads to fetch transaction data from the database. The default configuration runs eight threads, reducing disk‑I/O wait times and speeding up block catch‑up.

Wallet and PSBT updates

Three wallet commands that create partially signed Bitcoin transactions will default to PSBT version 2, the newer format for exchanging transaction data between wallets and signing devices. Applications can still request the older format if needed.

Security fixes

• A command‑execution vulnerability affecting non‑Windows systems was fixed. The flaw allowed an authenticated user with wallet creation rights to embed commands in a wallet name, which could be executed if the walletnotify feature was enabled. The fix treats wallet names as literal text.
• A memory‑exhaustion issue in the new internal web server and REST interface was addressed. The bug allowed unauthenticated connections to consume gigabytes of memory rapidly. After the fix, memory usage remains minimal during the same test.

Release schedule

Version 32 does not alter Bitcoin’s consensus rules. After the final testing period, the developers aim to publish the stable release on October 10.