https://www.theregister.co.uk/2018/01/09/meltdown_patch_anti_malware_conflict/

Microsoft's workaround to protect Windows computers from the Intel processor security flaw dubbed Meltdown has revealed the rootkit-like nature of modern security tools.

Some anti-malware packages are incompatible with Redmond's Meltdown patch, released last week, because the tools make, according to Microsoft, “unsupported calls into Windows kernel memory,” crashing the system with a blue screen of death. In extreme cases, systems fail to boot up when antivirus packages clash with the patch.