Regarding the Meltdown and Spectre exploits, as of this writing, the Intel® Xeon® W Family of processors are not on this list:
(The list can be found under the question, "Which Intel-based platforms are affected by or vulnerable to the issue?")
Is this simply an oversight or are they actually not affected?
Thank you for bringing this to our attention, let me help you on this matter.
Based on the link you mentioned, the Intel® Xeon® W-series is not listed on the vulnerability issue.
Our recommendation would checking with your motherboard maker or operating system developer for any update you can apply to your system.