The most recent FreeBSD security advisory which is a followup on the Spectre vulnerability can be read at:
https://www.freebsd.org/security/advisories/FreeBSD-SA-19:07.mds.asc
Briefly: The Intel HyperThreading technology has unsolvable flaw and must be disabled. You have to update your BIOS or to apply CPU microcode patches, then disable hyperthreading completely.
This affects all environments with different users (such as web hostings for example).
https://www.freebsd.org/security/advisories/FreeBSD-SA-19:07.mds.asc
Briefly: The Intel HyperThreading technology has unsolvable flaw and must be disabled. You have to update your BIOS or to apply CPU microcode patches, then disable hyperthreading completely.
This affects all environments with different users (such as web hostings for example).