Intel recently released a security patch to protect against a new set of vulnerabilities called Microarchitectural Data Sampling (MDS).
These vulnerabilities enable the ZombieLoad exploit, which threatens the security of Intel’s CPU platform.
Intel released microcode updates to patch this vulnerability, and Apple has outlined its own process for Mac users to ensure their devices are protected.
Apple states on its website that all modern Mac users are potentially vulnerable to this attack, and details how they can secure their devices against any potential exploit.
Full mitigation requires disabling hyper-threading, although this has a significant performance impact on the user’s device.
In its own testing, Apple found that disabling this feature showed a reduction in performance of up to 40%, adding that the severity of this performance hit will vary based on model, configuration, and workload.
To enable full mitigation for MDS vulnerabilities, Mac users must restart their devices in macOS Recovery and navigate to the Terminal app from the Utilities menu.
In the Terminal, users must enter the following commands:
Users can then restart their device, after which hyper-threading will be disabled and they will no longer be vulnerable to MDS exploits.