Ethereum Classic recently experienced a social engineering incident involving the Core-Geth client. The ethereumclassic/core-geth v1.13.0, released on September 14 without review by existing maintainers, was promoted as a security update. A small number of mining pool nodes temporarily switched to this version before reverting to the long-term maintained etclabscore/core-geth v1.12.23. The unreviewed version modified critical logic such as chain selection and node discovery, posing a potential risk of network split; the incident did not result in lost blocks, chain reorganization, fund loss, or service disruption. [Odaily]