InstallAware

Is there a runtime that includes the Spectre/Meltdown mitigation code? Or is it included in one of the listed runtimes:

Microsoft Visual C++ Runtime for Visual Studio 2017 v.15.2
Microsoft Visual C++ Runtime for Visual Studio 2017 v.15.4
Microsoft Visual C++ Runtime for Visual Studio 2017 v.15.7
Microsoft Visual C++ Runtime for Visual Studio 2017 v.15.9

None of these include Spectre/Meltdown mitigation code.

You may create your custom Runtime using the "Application Runtime Wizard".
https://www.installaware.com/mh5/desktop/runtime.htm