Some of the most devastating ransomware and Trojan malware variants depend on vulnerabilities in the Windows Server Message Block (SMB) Windows SMB is a protocol used by PCs for file and printer sharing, as well as for access to remote services. A patch was released by Microsoft for SMB vulnerabilities in March 2017, but many organizations and home users have still not applied it. In fact, our product telemetry has recorded 5,315 detections of Emotet and TrickBot in business networks in the last 30 days alone.”]
Source: https://blog.malwarebytes.com/101/2018/12/how-threat-actors-are-using-smb-vulnerabilities/