Preface: Emotet malware found in 2015. But he is still aggressive nowadays. It shown that it is a long life cyber attack product .

Details: Australian Cyber Security Centre (ACSC) released an advisory that Emotet malware widespread in rapidly. The Emotet malware is distributed mostly by means of phishing email that contains either links to malicious sites, or malicious attachments.
Since Emotet is a polymorphic design.Emotet is a polymorphic engine to mutate different values and operations. From observation, it now link with ransomware.
The change in shape of Emotet more or less proof that his design is equivalent as a cyber weapon. It provide the functions for infiltration. Meanwhile, after finished the mission. It can link to ransomware. Such design can avoid forensic investigator conduct the validations.

For more details, please refer to ACSC announcement. https://www.cyber.gov.au/threats/advisory-2019-131-emotet-malware-campaign