How do the Intel CPU security flaws affect Macs?

[Joshua5684]

I've been hearing a lot about recent Intel CPU exploits. One week, it seemed like there was a new one every day. Thankfully, within a few days, Intel usually has an update to fix it, but that left me wondering: "what about Mac?"

As far as I know, you can't update firmware on a Mac. Are these updates just included in MacOS updates?

[kpluck]

Apple can issue firmware updates as needed although with these latest exploits firmware updates can't fix the problem. The latest Intel exploits won't affect macOS hardware equipped with Apple's T1 or T2 chips. Macs without those chips are SOL.

 

-kp

[Kisai]

1 hour ago, Joshua5684 said:

I've been hearing a lot about recent Intel CPU exploits. One week, it seemed like there was a new one every day. Thankfully, within a few days, Intel usually has an update to fix it, but that left me wondering: "what about Mac?"

As far as I know, you can't update firmware on a Mac. Are these updates just included in MacOS updates?

The answer to that is basically "they do not", since Apple controls the firmware, and firmware pushes are part of updates to the OS.

 

One thing to keep in mind here is that doesn't mean the CPU can be patched. It just means that the firmware updates can be applied and thus less or no OS-level patching is required. It may be easier to just mitigate issues at the OS level if they affect more than one generation of Mac.

 

However doing that may mean the combination of Spectre, Meltdown and Zombieload mitigation might actually drop the CPU performance significantly more than patching at the microcode level in the firmware.