The Ethereum alarm clock smart contract vulnerability has led to hackers stealing approximately 200 ETH

ChainCatcher news, PeckShield monitoring shows that the Ethereum Alarm Clock smart contract has been exploited, allowing attackers to receive more ETH in refunds than expected by setting higher transaction fees. Normally, users calling the contract would only receive slightly more than their transaction fees in return. Currently, this vulnerability has led to the theft of approximately 204 ETH, worth about $260,000.

It is reported that the Ethereum Alarm Clock smart contract allows users to schedule future transactions by pre-determining the recipient address, sending amount, and transaction time. (source link)