LND, a Lightning Network node implementation, disclosed a channel-close flaw that can put an entire channel balance at risk in a reproduced maximum-loss scenario. A malicious channel peer could participate in a cooperative close, wait for one on-chain confirmation, and exploit a one-block Bitcoin reorganization that removes the closing transaction from the chain. The peer would also need to publish an earlier revoked commitment transaction, an outdated channel balance state that should trigger penalty transactions. Before the fix, LND could forget the cooperatively closed channel after its first confirmation and fail to broadcast those penalties after a reorganization. Repository history indicates that official protection begins with version 0.21.0, rather than the 0.20.0 cutoff cited in the disclosure, leaving standard releases below 0.21.0 exposed unless independently patched. Bastien Teinturier said no affected users were known, and the issue is specific to LND rather than evidence of a flaw in other Lightning implementations.