Does anyone know how to resolve missing kernel mitigation's?

I just ran a security scan on my Linux Server (Ubuntu 18.04.5 LTS with Kernel 4.15.0-143-generic #147-Ubuntu SMP and I like to know how to fix this. Anyone knows how to resolve the following issues:

Missing Linux Kernel mitigations for 'iTLB multihit' hardware vulnerabilities
Missing Linux Kernel mitigations for 'SSB - Speculative Store Bypass' hardware vulnerabilities
Missing Linux Kernel mitigations for 'MDS - Microarchitectural Data Sampling' hardware vulnerabilities
Missing Linux Kernel mitigations for 'TAA - TSX Asynchronous Abort' hardware vulnerabilities