I don't have detailed recommendation but obviously for your budget you should ...
1. prioritise more RAM
2. I suggest Ryzen Zen3
3. Prefer older generation AMD GPU for less hassle with Linux.
4. I prefer Asus mobos again for least hassle with Linux.
But let others chime in...
I myself bought a pre assembled Zen2 threadripper 3970x for similar use case, mostly VMs and fast code compilation, not really cybersecurity, from this business in Pune called Gtek who I'm very happy with.
Unless you want to DIY or have local sources you can ask them for a quote based on what you finalise.
Personally I wanted to avoid the hassle and risks of DIY.