Malware Research team at CheckPoint have discovered a new piece of fully-undetectable Mac malware, which according to them, affects all versions of Mac OS X, has zero detections on VirusTotal and is "signed with a valid developer certificate (authenticated by Apple)."
Dubbed DOK, the malware is being distributed via a coordinated email phishing campaign and, according to the researchers, is the first major scale malware to target macOS users.
Detailed report can be found here: OSX Malware is Catching Up, and it wants to Read Your HTTPS Traffic | Check Point Blog