Vulnerability · Published Oct 21, 2020 · Assigned by mitre
CVE-2020-26896
High 8.2
In plain English
A high-severity security flaw in the affected software. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 55% of all known vulnerabilities).
Official description
Prior to 0.11.0-beta, LND (Lightning Network Daemon) had a vulnerability in its invoice database. While claiming on-chain a received HTLC output, it didn't verify that the corresponding outgoing off-chain HTLC was already settled before releasing the preimage. In the case of a hash-and-amount collision with an invoice, the preimage for an expected payment was instead released. A malicious peer could have deliberately intercepted an HTLC intended for the victim node, probed the preimage through a colluding relayed HTLC, and stolen the intercepted HTLC. The impact is a loss of funds in certain situations, and a weakening of the victim's receiver privacy.