CVE-2021-47062

MEDIUM

Linux Kernel 5.11-5.11.20 - NULL Pointer Dereference in KVM SVM VMSA Encryption

Title source: llm
STIX 2.1

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.

Scores

CVSS v3 5.5
EPSS 0.0022
EPSS Percentile 12.7%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-476
Status published
Products (9)
Linux/Linux < 5.11
Linux/Linux 5.11
Linux/Linux 5.11.21 - 5.11.*
Linux/Linux 5.12.4 - 5.12.*
Linux/Linux 5.13
Linux/Linux ad73109ae7ec30d5bfb76be108e304f9f0af4829 - ba7bf5d6336aa9c0d977b161bfa420c56d46ee40
Linux/Linux ad73109ae7ec30d5bfb76be108e304f9f0af4829 - bd0cced2ae93195668f983d443f7f17e8efd24d2
Linux/Linux ad73109ae7ec30d5bfb76be108e304f9f0af4829 - c36b16d29f3af5f32fc1b2a3401bf48f71cabee1
linux/linux_kernel 5.11 - 5.11.21
Published Feb 29, 2024
Tracked Since Feb 18, 2026