How severe is CVE-2021-47062?

CVE-2021-47062 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-47062 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47062?

CVE-2021-47062 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47062?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2021-47062 have an EU (EUVD) identifier?

Yes. CVE-2021-47062 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33710.

When was CVE-2021-47062 published?

CVE-2021-47062 was published on 2024-02-29 and last updated on 2026-06-17.

CVE-2021-47062

CVE-2021-47062 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33710
Weakness: CWE-476
Affected product: Linux Linux Kernel
Published: 2024-02-29
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Use online_vcpus, not created_vcpus, to iterate over vCPUs Use the kvm_for_each_vcpu() helper to iterate over vCPUs when encrypting VMSAs for SEV, which effectively switches to use online_vcpus instead of created_vcpus. This fixes a possible null-pointer dereference as created_vcpus does not guarantee a vCPU exists, since it is updated at the very beginning of KVM_CREATE_VCPU. created_vcpus exists to allow the bulk of vCPU creation to run in parallel, while still correctly restricting the max number of max vCPUs.

Frequently asked questions

What is CVE-2021-47062?: In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Use online_vcpus, not created_vcpus, to iterate over vCPUs Use the kvm_for_each_vcpu() helper to iterate over vCPUs when encrypting VMSAs for SEV, which effectively switches to use online_vcpus instead of created_vcpus. This fixes a possible null-pointer dereference as created_vcpus does not guarantee a vCPU exists, since it is updated at the very beginning of KVM_CREATE_VCPU. created_vcpus exists to allow the bulk of vCPU creation to run in parallel, while still correctly restricting the max number of max vCPUs.
How severe is CVE-2021-47062?: CVE-2021-47062 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-47062 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47062?: CVE-2021-47062 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47062?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47062 have an EU (EUVD) identifier?: Yes. CVE-2021-47062 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33710.
When was CVE-2021-47062 published?: CVE-2021-47062 was published on 2024-02-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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