Downfall vulnerability may affect Intel Macs; usual precautions

A newly-discovered Downfall vulnerability found in Intel chips may affect older Macs powered by these processors …

A new variant of Spectre and Meltdown

Back in 2018, a major security flaw was found in both Intel and ARM chips, which could be exploited by two attacks known as Spectre and Meltdown.

It was a huge deal because it was a hardware-level bug affecting about a decade’s worth of processors, and while Apple successfully patched it, that came at the cost of a performance hit.

A year later, a new variant was discovered – but this one couldn’t be exploited by machines running macOS, so was only a concern to those running Windows on their Mac.

Downfall vulnerability

Now security researcher Daniel Moghimi has discovered an additional variant, known as the Downfall vulnerability.

Downfall attacks target a critical weakness found in billions of modern processors used in personal and cloud computers. This vulnerability, identified as CVE-2022-40982, enables a user to access and steal data from other users who share the same computer. For instance, a malicious app obtained from an app store could use the Downfall attack to steal sensitive information like passwords, encryption keys, and private data such as banking details, personal emails, and messages […]

The vulnerability is caused by memory optimization features in Intel processors that unintentionally reveal internal hardware registers to software. This allows untrusted software to access data stored by other programs, which should not normally be accessible.

The flaw is found in every Intel CPU from Skylake through to the 12th-gen Alder Lake.

Unclear whether Macs are vulnerable

If you have an Intel Mac from 2016 onward (or a late-2015 iMac), then the flaw is present in your CPU.

However, as Macworld notes, this doesn’t necessarily mean that the vulnerability can actually be exploited on Macs.

Macs are sort of unique. Intel Macs used custom motherboards and firmware, some even have the T2 processor that manages a lot of stuff. It doesn’t seem as though any of this would necessarily prevent an attack using the Downfall vulnerability, but it’s hard to know until we get confirmation from Apple. We’ve reached out for clarification and will update this article if someone responds.

The usual precautions apply

Either way, the best protection against these sorts of exploits is to follow standard cybersecurity precautions to block malware which could take advantage of them. You’ll find full details in that link, but the quick checklist is:

• Only ever download apps from the Mac App Store and trusted developers
• Use strong, unique passwords for every website
• Don’t use real info when answering standard security questions
• Use two-factor authentication whenever it is offered
• Never click on links sent via email unless you are certain it is genuine
• Guard against bank fraud
• Ideally, never access sensitive sites on public wifi hotspots
• If you have no choice, then use a trusted VPN service

Photo: Vishnu Mohanan/Unsplash