Emotet is a malware infection that is distributed through spam campaigns with malicious attachments. If a user opens the attachment, malicious macros or JavaScript will download the Emotet DLL and load it into memory using PowerShell.

Once loaded, the malware will search for and steal emails to use in future spam campaigns and drop additional payloads such as TrickBot or Qbot that commonly lead to ransomware infections.

Source: bleepingcomputer.com