CVE-2021-47255

kvm: LAPIC: Restore guard to prevent illegal APIC register access

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:

kvm: LAPIC: Restore guard to prevent illegal APIC register access

Per the SDM, "any access that touches bytes 4 through 15 of an APIC
register may cause undefined behavior and must not be executed."
Worse, such an access in kvm_lapic_reg_read can result in a leak of
kernel stack contents. Prior to commit 01402cf81051 ("kvm: LAPIC:
write down valid APIC registers"), such an access was explicitly
disallowed. Restore the guard that was removed in that commit.

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: kvm: LAPIC: Restaurar protección para evitar el acceso ilegal al registro APIC. Según el SDM, "cualquier acceso que toque los bytes 4 al 15 de un registro APIC puede causar un comportamiento indefinido y no debe ejecutarse ". Peor aún, dicho acceso en kvm_lapic_reg_read puede resultar en una fuga del contenido de la pila del kernel. Antes de confirmar 01402cf81051 ("kvm: LAPIC: anotar registros APIC válidos"), dicho acceso se prohibía explícitamente. Restaura la guardia que se eliminó en esa confirmación.

*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

2024-04-10 CVE Reserved
2024-05-21 CVE Published
2024-05-22 EPSS Updated
2024-08-04 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CAPEC

References (5)

URL	Tag	Source
https://git.kernel.org/stable/c/01402cf81051f796dac7c60ca11d6147153ca46a	Vuln. Introduced

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84	2021-06-23
https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5	2021-06-23
https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210	2021-06-23
https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6	2021-06-09

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"				>= 5.3 < 5.4.128 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.3 < 5.4.128"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 5.3 < 5.10.46 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.3 < 5.10.46"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 5.3 < 5.12.13 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.3 < 5.12.13"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 5.3 < 5.13 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.3 < 5.13"		en		Affected