According to SlowMist Yuxian analysis, the attack on the cross-chain bridge project 402Bridge appears to have originated from a private key leak, and the possibility of insider involvement cannot be ruled out. The 402bridge.fun domain name ceased service just two days after registration. The attacker's address profited approximately 4.2 ETH and has transferred the stolen funds to the Arbitrum network. Currently, no further movement of the stolen funds has been observed. This is the first public security incident involving services related to the 402 protocol.