If you launch Windows update in Windows 10 and watch you'll see that the Malware Definitions for Windows Defender also get updated. I think you can also launch Windows Security and do a straight update from there too. Anyway, I always run Windows Update at boot up first thing before I do anything else. In general I find the Malware Definitions are updated near to daily.
Windows Defender had originally Quarantined the offending "malware" as a trojan. From there I had the option to delete or restore - I deleted it yesterday...then I went back today and performed the below and didn't get any further indication of an issue from Windows Defender.