Missed Zenbleed fix for Steam Deck is on track to ship

FIFA 23 on Steam Deck
(Image credit: Ben Wilson | Windows Central)

What you need to know

  • A Zenbleed bug impacted AMD's Zen 2 processors last month.
  • The issue has since been patched, but the code related to the Steam Deck was missing the Zenbleed erratum list.
  • The code has been included in the list, automatically enabling the fallback fix until a microcode update is available.

In July, we reported the Zenbleed vulnerability that affected AMD's Zen 2 processors. A serious threat that can cause the leak of personal and sensitive credentials such as user logins and encryption keys. Moreover, attackers can leverage the bug to access your information remotely. 

And while the issue has since been patched via a microcode update, it missed the code related to the Steam Deck. This means that the AMD Custom APU 0405, representing Valve's Steam Deck, was not factored in initially as part of the affected processors, as spotted by GamingOnLinux.

However, the CPU variant has since been incorporated into the Zenbleed erratum list, automatically enabling the fallback fix in a bid to ensure that the Steam Deck is also covered, as highlighted in the patch notes:

"Commit 522b1d69219d ("x86/cpu/amd: Add a Zenbleed fix") provided a fix for the Zen2 VZEROUPPER data corruption bug affecting a range of CPU models, but the AMD Custom APU 0405 found on SteamDeck was not listed, although it is clearly affected by the vulnerability.

Add this CPU variant to the Zenbleed erratum list, in order to unconditionally enable the fallback fix until a proper microcode update is available."

Performance effects on the Steam Deck

Several users are skeptical about this patch because of the impact it might have on the device's overall performance. Granted, the Steam Deck is essentially a handheld gaming console, but its offering stretches far beyond gaming. 

It ships with a fully-fledged desktop mode, allowing you to do practically anything, even installing a browser. It's important that all safety measures are implemented to prevent any unfortunate consequences in the future. As such, it's quite possible that Steam Deck owners might soon receive a SteamOS upgrade.

Kevin Okemwa

Kevin Okemwa is a seasoned tech journalist based in Nairobi, Kenya with lots of experience covering the latest trends and developments in the industry. With a passion for innovation and a keen eye for detail, he has written for leading publications such as OnMSFT, MakeUseOf, and Windows Report, providing insightful analysis and breaking news on everything revolving around the Microsoft ecosystem. While AFK and not busy following the ever-emerging trends in tech, you can find him exploring the world or listening to music.