Need help reattaching heat sink to LM2 Aerostuder

In the process of clearing a rather nasty jam from my Mini 2 I discovered the heat sink can be unscrewed from the hotend. After clearing the jam and putting all the parts back together I noticed a large amount of plastic leaking from the hole where the heat sink screws into the hot end.

I there seemed to be some grey paste that looks like it had probably been applied to the threads of the heat sink. I’m assuming I’m going to need to acquire and apply some of this stuff to prevent further leakages. Is it simply the same thermal paste that you would use to attach a cooler to a CPU?

After a bit of research I’m leaning more heavily on “thermal glue” vs “thermal paste” but I’m hoping to get some confirmation before it try it.

Check out this guide.

https://e3d-online.dozuki.com/Guide/Titan+Aero+Assembly/23

Around step 3 or so. The grey paste is probably anti-seize to make it easy to take apart again if needed.