TECH NEWS – As many as six generations of Intel processors can expose sensitive data due to a vulnerability, and fixing the bug can result in a severe performance hit.

The CPU vulnerability, called Downfall, is scary because it affects not just one generation of processors, but six, so everything from 6th generation (i3/5/7-6xxx) Skylake processors to 11th generation Rocket Lake and Tiger Lake (i3/5/7/9-11xxx) processors are affected. (Tiger Lake refers to the laptop processor family!) The vulnerability has also been published on a web page, and Intel has responded by posting Intel-SA-00828.

The flaw is related to memory optimization features in Intel processors. Software can access specific protected hardware registers when it should not. In processors supporting AVX2 and AVX-512, the Gather Instructions are accessed, allowing the malware to access our applications and programs and to gain access to our encryption keys and passwords, which can be transmitted. Unfortunately, the vulnerability also affects cloud operators, so all customers using the same cloud computer can have their data and login credentials stolen by Downfall!

AVX instructions are essential in many intensive processes (used by many rendering and encoding applications beyond subprocesses and libraries). It’s worth checking the product information website of your motherboard, and if the manufacturer (e.g., Gigabyte, Asus, MSI…) recommends updating the BIOS, do it. However, be aware that it will have a minor side effect.

A BIOS update that includes a microcode fix will often reduce performance, and it is what we have seen with Downfall’s folding. Initial testing by Phoronix tried the patch and the Linux kernel patch and found a significant reduction in performance. Although AVX instructions were less used in games, they are also affected. Emulation is more severely affected: RPCS3, which emulates PlayStation 3 games, relies heavily on the AVX-512 instruction set!

For those planning to upgrade to Intel, switch to the 12th-generation Alder Lake and 13th-generation Raptor Lake processors: these CPUs are unaffected.

Source: PCGamer