Bitcoin Lightning fix blocks a probe linking private channels to onchain funding

Lightning Development Kit (LDK), software used to build Bitcoin Lightning applications, has a privacy fix that blocks a documented probe linking an unannounced channel to the Bitcoin output backing it. The probe exploited how LDK forwarded onion messages, turning a guessed channel identifier into confirmation of a connection between two suspected nodes. Bitcoin Optech highlighted the change on October 30 . An unannounced channel stays out of the public network map, but that alone did not prevent LDK’s message-forwarding lookup from confirming its funding link. A real short-channel ID, or SCID, works like blockchain coordinates.