CVE-2021-47110

x86/kvm: Disable kvmclock on all CPUs on shutdown

Severity Score

"-"

*CVSS v-

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track

*SSVC

Descriptions

In the Linux kernel, the following vulnerability has been resolved:

x86/kvm: Disable kvmclock on all CPUs on shutdown

Currenly, we disable kvmclock from machine_shutdown() hook and this
only happens for boot CPU. We need to disable it for all CPUs to
guard against memory corruption e.g. on restore from hibernate.

Note, writing '0' to kvmclock MSR doesn't clear memory location, it
just prevents hypervisor from updating the location so for the short
while after write and while CPU is still alive, the clock remains usable
and correct so we don't need to switch to some other clocksource.

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: x86/kvm: deshabilite kvmclock en todas las CPU al apagar Actualmente, deshabilitamos kvmclock desde el enlace machine_shutdown() y esto solo sucede para la CPU de arranque. Necesitamos deshabilitarlo para todas las CPU para protegernos contra la corrupción de la memoria, por ejemplo, al restaurar desde la hibernación. Tenga en cuenta que escribir '0' en kvmclock MSR no borra la ubicación de la memoria, solo evita que el hipervisor actualice la ubicación, por lo que durante un breve período después de la escritura y mientras la CPU aún está activa, el reloj permanece utilizable y correcto, por lo que no lo necesitamos. para cambiar a alguna otra fuente de reloj.

*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

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2024-03-04 CVE Reserved
2024-03-15 CVE Published
2024-03-16 EPSS Updated
2024-08-04 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CAPEC

References (4)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/stable/c/9084fe1b3572664ad276f427dce575f580c9799a	2021-06-10
https://git.kernel.org/stable/c/3b0becf8b1ecf642a9edaf4c9628ffc641e490d6	2021-06-10
https://git.kernel.org/stable/c/1df2dc09926f61319116c80ee85701df33577d70	2021-06-10
https://git.kernel.org/stable/c/c02027b5742b5aa804ef08a4a9db433295533046	2021-05-07

URL	Date	SRC

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"				< 5.4.125 Search vendor "Linux" for product "Linux Kernel" and version " < 5.4.125"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.10.43 Search vendor "Linux" for product "Linux Kernel" and version " < 5.10.43"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.12.10 Search vendor "Linux" for product "Linux Kernel" and version " < 5.12.10"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.13 Search vendor "Linux" for product "Linux Kernel" and version " < 5.13"		en		Affected