On Wednesday, Windows users – both home and enterprise – started sharing details on a strange update delivered by Microsoft.
The update itself used a string of random characters in the description, along with resource URLs using a similar format pointed at .gov, .mil, and .edu addresses.
On the Microsoft Answers community, a user posted details of the update, delivered at 0430 their time, which sparked a number of conversations.
Searching for the string that's present in the update's details note reveals a number of other customers who got the same update – many of them speculating that the Windows update system was somehow compromised.
However, when examining the logs of someone who was able to access the update, the file is clearly marked as a test. Microsoft confirmed this later in the afternoon.
"We incorrectly published a test update and are in the process of removing it," a spokesperson said in an emailed statement.
While the questionable download may appear in the list of available updates (marked as Important), a re-scan of updates on the system will clear it from the list.
By Wednesday afternoon, the file was no longer available. It isn't clear what files were modified by the update if it was downloaded and installed prior to removal. We've asked Microsoft for additional details, and will update if there is further information.
The bottom line is that all indications point to a mistake on Microsoft's part, and not a compromise of the Windows Update system.