I have check whether my computer has been affected by recent CPU attack(Meltdown and Spectre)
So I checked using

https://github.com/raphaelsc/Am-I-affected-by-Meltdown

and then says...

System affected! Please consider upgrading your kernel to one that is patched with KAISER

My kali linux kernel is 4.13.0-kali1-amd64
How can I upgrade kernel that has benn patched with KAISER??