Malware WinOS (ValleyRAT): Trojan Family July 10, 2026 ♡Follow0 WinOS, also known as ValleyRAT, is a trojan family used by Silver Fox in their operations. Discovered from: New MODBEACON RAT Uses gRPC Streaming for Encrypted C2 Traffic Silver FoxtrojanValleyRATWinOSWinOS (ValleyRAT)