Wu said that according to Scam Sniffer monitoring, a user lost 143.45 ETH (about 460,800 US dollars) yesterday due to transaction simulation fraud. Transaction simulation is a feature in the Web3 wallet that allows users to view the expected results of a transaction before signing. However, the attacker took advantage of the delay between transaction simulation and execution, and created a phishing website to tamper with the on-chain status immediately after the transaction was submitted. Attack process: The phishing website initiates a "Claim" ETH transfer request, the wallet simulates receiving a small amount of ETH, the back-end modifies the contract status, and the actual transaction depletes the wallet assets.