Microsoft did patch Windows 10's preview build 10240, the code expected to be the final release and handed to testers six days ago. Computerworld triggered a manual check for updates on Windows 10 build 10240 within minutes of Microsoft sounding the alert; the PC found the update, then automatically downloaded and installed it.
Today's sudden update was the first since January, when Microsoft shut down its public advance notification service for pending security updates, including out-of-band patches like MS15-078. At the time, Microsoft said it would use other ways to communicate the urgency of an out-of-band update to customers, but it did not elaborate.
Microsoft used the Twitter account of its security response center and that group's blog to announce the availability of MS15-078 today.
The last out-of-band security update from Microsoft was in November 2014, when it issued a patch for a bug hackers were already exploiting in its Windows Server software.
The MS15-078 update can be downloaded and installed via the Windows Update service, as well as through Windows Server Update Services (WSUS) to patch Windows Vista, Windows 7, Windows RT and RT 8.1, Windows 8 and 8.1, Windows 10, Windows Server 2008 and 2008 R2, and Windows Server 2012 and 2012 R2.
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