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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/ba7bf5d6336aa9c0d977b161bfa420c56d46ee40	Patch
https://git.kernel.org/stable/c/bd0cced2ae93195668f983d443f7f17e8efd24d2	Patch
https://git.kernel.org/stable/c/c36b16d29f3af5f32fc1b2a3401bf48f71cabee1	Patch
https://git.kernel.org/stable/c/ba7bf5d6336aa9c0d977b161bfa420c56d46ee40	Patch
https://git.kernel.org/stable/c/bd0cced2ae93195668f983d443f7f17e8efd24d2	Patch
https://git.kernel.org/stable/c/c36b16d29f3af5f32fc1b2a3401bf48f71cabee1	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2024-02-29 23:15

Updated : 2024-12-10 16:43

NVD link : CVE-2021-47062

Mitre link : CVE-2021-47062

CVE.ORG link : CVE-2021-47062

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

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