// For flags

CVE-2021-47062

KVM: SVM: Use online_vcpus, not created_vcpus, to iterate over vCPUs

Severity Score

"-"
*CVSS v-

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

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.

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: KVM: SVM: use online_vcpus, no creado_vcpus, para iterar sobre vCPU. Use el asistente kvm_for_each_vcpu() para iterar sobre vCPU al cifrar VMSA para SEV, que efectivamente cambia para usar online_vcpus en lugar de creado_vcpus. Esto corrige una posible desreferencia de puntero nulo ya que create_vcpus no garantiza que exista una vCPU, ya que se actualiza al comienzo de KVM_CREATE_VCPU. create_vcpus existe para permitir que la mayor parte de la creación de vCPU se ejecute en paralelo, al mismo tiempo que restringe correctamente la cantidad máxima de vCPU máximas.

*Credits: N/A
CVSS Scores
Attack Vector
-
Attack Complexity
-
Privileges Required
-
User Interaction
-
Scope
-
Confidentiality
-
Integrity
-
Availability
-
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-02-29 CVE Reserved
  • 2024-02-29 CVE Published
  • 2024-03-01 EPSS Updated
  • 2024-08-04 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.11 < 5.11.21
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.11 < 5.11.21"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.11 < 5.12.4
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.11 < 5.12.4"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.11 < 5.13
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.11 < 5.13"
en
Affected