CLN: Self-Referential Channel Announcement DoS disclosure
In briefCLN: Self-Referential Channel Announcement DoS Disclosure
SummaryCore Lightning v25.02 through v26.04 crash on a channel_announcement whose two node IDs are identical, and the node stays down across restarts until an operator manually removes the stored record. An attacker needs only an unspent 2-of-2 output, so the attack costs nothing beyond on-chain fees. The fix in v26.04.1 rejects announcements where node_id_1 is not lexicographically less than node_id_2.