CMAKE_VS_PLATFORM_TOOLSET_VERSION contains only first two components of version

When setting cmake ... -Tv142,version=14.20.27508,host=x64 the CMAKE_VS_PLATFORM_TOOLSET_VERSION variable is only populated with the first two components of the version, “14.20”. I need to pass the entire version, “14.20.27508” to msbuild for a legacy external project. Is there a way to get the full version other than manually parsing the CMAKE_GENERATOR_TOOLSET for the version key?