Ten Days of Rain was a destructive distributed-denial-of-service incident that began on March 4, 2011, targeting South Korean government websites and the network of U.S. Forces Korea. A botnet of compromised South Korean hosts disrupted the availability of multiple targets according to a preconfigured ten-day schedule. When that window expired, the malware stopped its denial-of-service activity and rendered infected hosts inoperable, forcing full restoration of operating systems, applications, and user data.