Google Information Security researcher Tavis Ormandy recently discovered a vulnerability with Zen 2 processors: “Zenbleed”. In layman’s terms, this exploit can allow “the theft of protected information from the CPU, such as encryption keys and user logins,” according to Tom’s Hardware. Any Zen 2-based processor is affected: the Ryzen 3000/4000/5000 series, and AMD’s EPYC data center processors. PS5, Xbox Series consoles, and the Steam Deck – which Valve have reported has similar performance to the Ryzen 3000 series – could also potentially be affected since they are using Zen 2 APUs, although it’s not clear at this point whether that’s actually the case.
Microcode has already been submitted to the Linux kernel, so perhaps Steam Deck users will get this patch in a future SteamOS update if Valve sees to it. There is a software workaround that you can use in the meantime by installing msr-tools, then with it set the “chicken bit” on all cores, but I don’t recommend this. Not only will this require unlocking the file system, but Ormandy warns that this “may have some performance cost.”