[SlowMist Cosine: 402Bridge attack caused by private key leak, possibly involving insider actions] SlowMist Cosine analysis indicates that the cross-chain bridge project 402Bridge was attacked due to a private key leak, and the possibility of insider involvement cannot be ruled out. The domain name 402bridge.fun ceased service just two days after registration, and there have been no further movements of the stolen funds so far. This is the first publicly disclosed security incident related to the 402 protocol's services. SlowMist Cosine stated that this incident is not a typical case of collective malicious behavior by the project team.