The Department of Homeland Security and the FBI have jointly announced detection of a "BOTNET" operated by "cyber actors" of the North Korean government. They are targeting the media, aerospace, financial, and critical infrastructure sectors. They've identified IP addresses associated with a distributed malware system called DeltaCharlie, that manages North Korea’s distributed denial-of-service (DDoS) botnet infrastructure.

The HIDDEN COBRA group primarily targets computers running older, unsupported, versions of Microsoft Windows. They also target Adobe's Flash Player. The vulnerabilities exploited are known, so the simple cure is to update your system to later versions of Windows or to apply security patches.