The Emotet botnet is now using malicious email attachment that pretends to be made by Windows 10 Mobile. Microsoft Word documents contain malicious macros that will download and install the malware when enabled. Once installed, the malware will steal a victim’s email to use in additional spam campaigns and download other malware such as TrickBot and QBot, which commonly lead to network-wide ransomware attacks. If you receive an email with a Word document stating it was made in Windows 10 mobile, do not enable editing or content, and immediately trash it.
Source: https://www.bleepingcomputer.com/news/security/epic-fail-emotet-malware-uses-fake-windows-10-mobile-attachments/