Bitcoin Core patches three security flaws, one could halt block building for miners

Bitcoin Core, the software used to run bitcoin nodes, has disclosed three security vulnerabilities. According to The Block and Decrypt, all three have already been patched. Both reports appeared on 11 November 2026.

The most serious flaw is rated high severity. It affects block template creation, the step where a miner assembles the next block. Decrypt reports that it could stop a miner from building new blocks. The other two issues are described as denial-of-service and privacy problems. Decrypt stresses that none of the three is about coin theft.

Because the fixes are already released, the reports do not describe an ongoing attack. The sources do not name the affected software versions, the dates of the patches, or any known cases of exploitation. They also do not say how many nodes or miners ran an unpatched release when the flaws were disclosed. Until more detail is published, readers should rely only on these points.