mach_kernel appeared

Hi all,

Just noticed mach_kernel appeared between Library and System at main level of HD. Don't think it was there before latest security update, but don't know for sure. Anyway, the question is, what to do about it. I found an old thread with the same issue back in 10.8.5 in 2013, but don't know if the fix would still be the same. Specific instructions appreciated. Also curious if others have found this issue.

Thanks!