CVE-2021-46977: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Disable preemption when probing user return MSRs Disable preemption when probing a user return MSR via RDSMR/WRMSR. If the MSR holds a different value per logical CPU, the WRMSR could corrupt the host's value if KVM is preempted between the RDMSR and WRMSR, and then rescheduled on a different CPU. Opportunistically land the helper in common x86, SVM will use the helper in a future commit.

Affected products

• Linux Linux Kernel: from 5.5, before 5.10.38 (fixed in 5.10.38); from 5.11, before 5.11.22 (fixed in 5.11.22); from 5.12, before 5.12.5 (fixed in 5.12.5); version 5.13 only

Published 2024-02-28. Last modified 2026-08-04.