Upbit suffered a cryptocurrency-exchange breach on 27 November 2019 when 342,000 ETH was transferred from its Ethereum hot wallet to attacker-controlled addresses, prompting service suspensions, cold-wallet transfers, and exchange-side tracing. Subsequent blockchain analysis described multi-hop laundering through exchanges and swap services, and South Korea's National Police Agency later attributed the theft to North Korea based on infrastructure, vocabulary, asset-flow, and FBI-cooperation evidence.