VERY IMPORTANT

Malicious spam (malspam) using zipped JavaScript (.js) files as email attachments--this is a well-established tactic used by cyber criminals to distribute malware. I've written diaries discussing such malspam in July 2015, September 2015, and February 2016. I've run across plenty of examples since then, but I've focused more on Microsoft Office documents instead of .js files. I last documented .js-based malspam in May 2018.