The claim is supported by multiple independent secondary reports. 'Umbra shuts front end after hackers move stolen funds through protocol' says Umbra took the front end offline after about $800,000 in stolen funds passed through the protocol and that the smart contracts remain operational. Odaily's '隐私协议 Umbra 关闭前端以阻止攻击者转移 Kelp 相关被盗资金' matches the same key details and specifically says the related transactions remain traceable on-chain. PANews' '隐私协议Umbra关闭前端以阻止Kelp攻击者利用其转移资金' independently repeats those points and notes the hosted frontend was placed into maintenance mode. Confidence is only medium because no direct Umbra primary post or official site statement was retrievable in this run, and the exact upstream source appears to be cited secondhand.