AMD & Intel Roll Out New Linux Updates For Today's Patch Tuesday

Today's Patch Tuesday is a busier one than normal for the quarter. Both AMD and Intel have rolled out new updates for Linux customers among other security disclosures today. Thankfully though the vulnerabilities don't appear to be too widespread or impactful.

Hitting the Linux kernel source tree minutes ago was the patch x86/CPU/AMD: Prevent improper isolation of shared resources in Zen2's op cache. This is a patch to make sure resources are not improperly shared in the CPU's op cache and cause instruction corruption.

That AMD patch is specific to older Zen 2 processors and correlates to today's CPU op cache corruption security bulletin. AMD-SB-7052 notes that a CPU operation cache issue on Zen 2 could lead to incorrect instructions being executed at a higher privilege level.

AMD also issued new bulletins concerning their Windows drivers and potential vulnerabilities on a variety of Ryzen CPUs. A "MilanLaunchy" disclosure was also made for leveraging existing known vulnerabilities to allow the execution of arbitrary unsigned bootloaders on AMD EPYC Milan CPUs but is already corrected with newer system firmware.

AMD also acknowledged new security research of TDXRay as a side-channel analysis of Intel TDX. AMD's SEV-SNP though isn't impacted by TDXRay. More details on today's AMD disclosures can be found via the AMD product security center.

Meanwhile on the Intel side for Linux users today they released Intel CPU Microcode 20260512. This affects an Intel security issue as well as various functional issues affecting Arrow Lake, Lunar Lake, Panther Lake and Xeon Emerald Rapids / Sapphire Rapids / Sierra Forest / Granite Rapids processors.

INTEL-SA-01420 is due to the potential exposure of sensitive information caused by shared microarchitectural predictor state when dealing with non-root VMs. This affects Arrow Lake / Lunar Lake / Panther Lake and mitigated by the new CPU microcode. The functional issues fixed for the other CPUs appear to be scattered throughout with none of those changes appearing too pressing.