Privacy protocol Umbra has temporarily shut down its frontend website following a significant hack on the Kelp protocol, which resulted in over $280 million in losses. Umbra's decision aims to hinder the transfer of approximately $800,000 in stolen funds through its platform. The shutdown is described as a "maintenance mode" measure, pending confirmation that recovery efforts remain unaffected. The attack, suspected to involve North Korean hackers, attempted to move funds from Ethereum to Bitcoin using protocols like Umbra. Roman Storm, co-founder of Tornado Cash, cautioned that merely shutting down the frontend might not shield Umbra from regulatory scrutiny. He highlighted that authorities might interpret frontend changes as control over the entire protocol. Umbra clarified that its protocol is designed to protect recipient identities and that all stolen funds are traceable, with security researchers already engaged.