vulnerability
Red Hat: CVE-2021-47112: kernel: x86/kvm: Teardown PV features on boot CPU as well
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:L/AC:L/Au:S/C:N/I:N/A:C) | Mar 15, 2024 | Jul 9, 2025 | Jul 10, 2025 |
Severity
5
CVSS
(AV:L/AC:L/Au:S/C:N/I:N/A:C)
Published
Mar 15, 2024
Added
Jul 9, 2025
Modified
Jul 10, 2025
Description
In the Linux kernel, the following vulnerability has been resolved:
x86/kvm: Teardown PV features on boot CPU as well
Various PV features (Async PF, PV EOI, steal time) work through memory
shared with hypervisor and when we restore from hibernation we must
properly teardown all these features to make sure hypervisor doesn't
write to stale locations after we jump to the previously hibernated kernel
(which can try to place anything there). For secondary CPUs the job is
already done by kvm_cpu_down_prepare(), register syscore ops to do
the same for boot CPU.
Solution
no-fix-redhat-rpm-package
References
Rapid7 Labs
2026 Global Threat Landscape Report
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