An attack on the Litecoin network resulted in a 13-block chain reorganization to undo the effects of a denial-of-service attack that exploited a vulnerability in the Mimblewimble Extension Block protocol. The vulnerability was privately patched between March 19 and 26, but not publicly disclosed until after the attack. The attack allowed invalid transactions to be processed before the network corrected them.
A security update has been released, and users are advised to upgrade to the latest version of Litecoin Core. Researchers have questioned the handling of the vulnerability, citing the timeline of events and the fact that the fix was not publicly disclosed until after the attack.
The incident highlights the challenges faced by older proof-of-work networks in responding to security threats and the importance of timely disclosure and patching of vulnerabilities.