Lightning tightens invoice rules after reported attack made Bitcoin withdrawals look unpaid

Lightning developers tightened BOLT11, the Lightning Network’s invoice standard, on Oct. 19 to require software to reject ambiguous payment-hash and payment-secret fields. The change follows a developer’s account of an attack that made completed Bitcoin withdrawals appear unpaid. The merged change targets software components reading the same signed payment request differently. A payment hash identifies the payment a component is tracking. Bitcoin Optech highlighted the rule change on Oct. 23. In practical terms, a service could track a withdrawal under one hash while its node executes a payment using another. The service could then mistake the completed withdrawal for an unpaid one, creating an opening for further payouts. The failure sits in the connection between payment execution and the service’s accounting.

First reported by CryptoSlate. This page is a short excerpt; the full text is theirs.