Firstly, chances are good that your Mac is not at risk for the first time. Do you want to check?
- Go to the Apple menu, select About this Mac
- Click the System Report … button
- Click the Hardware title in the sidebar
In the Hardware Overview section (it's relatively short), look for the term hyper- threading. Don't you see? You can ignore this problem.
If your Mac supports hyper-threading, you should look at this official Apple Support document.
Before you do anything, note:
Testing performed by Apple in May 2019 showed as much as a 40 percent reduction in performance with tests that include multithreaded workloads and public references. Performance tests are performed using specific Macs. Actual results will vary depending on model, configuration, usage, and other factors.
Although there are no known challenges affecting customers at the time of this writing, customers who believe in the computer have an increased risk of attack using the Terminal app to activate an additional CPU instruction and disable processing technology that provides full protection against these vulnerabilities.
No known exploits. Only the potential for exploitation. Requested is forearmed.
A piece of a PR thing for Apple, but a mighty problem for Intel.
UPDATE: There are some questions as to whether a lack of override supports Mac in safe haven from Intel vulnerability. The problem is, if you disable hyper-threading (and add the extra CPU instruction), you'll be safe. But the question is, if your Mac doesn't support hyper-threading in the first place, does that mean the Mac is not susceptible to the problem?
If anyone knows the final answer to this, you can reach out .