Receiving multiple e-mails from "firstname.lastname@example.org" regarding this and similarly patterned URLs:
This email is from the Barracuda Web Security Gateway. We have detected and blocked the download of: VIRUS Win.Trojan.Generic-6840770-0
from the server:au.download.windowsupdate.com
It looks like this is just virus definitions for our Microsoft Antivirus. This is still occuring with spyware definitions 2.0.5961 (2019-02-04 12:35:24) and antivirus definitions 188.8.131.5231 (2019-02-04 10:23:15). Both of these are currently the latest of each type.