From [1]: "Most update mechanisms are protected by signatures or other cryptographic primitives. However there were some indications that older CPU models (unt

From [1]: "Most update mechanisms are protected by signatures or other cryptographic primitives. However there were some indications that older CPU models (until around 2013) do not have a strong cryptographic protection and thus would accept custom updates." [1]: https://media.ccc.de/v/34c3-9058-everything_you_want_to_know_about_x86_microcode_but_might_have_been_afraid_to_ask https://media.ccc.de/v/34c3-9058-everything_you_want_to_know...