Intel Atom processors (shared predictor transient execution): Shared microarchitectural predictor state influences

Impact

Shared microarchitectural predictor state influences transient execution on Atom parts, allowing local information disclosure. Same advisory wave as the branch privilege injection work; relevant to Atom-based appliances inside the datacenter footprint.

Who can reach it

Local authenticated code on an affected Atom platform.

What to do

Mitigated by an Intel microcode update plus OS/hypervisor changes. Microcode for this class is normally shipped by your distribution as an early-loadable image, so you can deploy it with a package update and a reboot without waiting for an OEM BIOS release - that distinction is the difference between a week and a quarter. Verify after reboot by reading /sys/devices/system/cpu/vulnerabilities/ rather than assuming the package took effect.

References