CVE-2021-43056

kernel: ppc: kvm: allows a malicious KVM guest to crash the host

Severity Score

5.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

An issue was discovered in the Linux kernel for powerpc before 5.14.15. It allows a malicious KVM guest to crash the host, when the host is running on Power8, due to an arch/powerpc/kvm/book3s_hv_rmhandlers.S implementation bug in the handling of the SRR1 register values.

Se ha detectado un problema en el kernel de Linux para powerpc versiones anteriores a 5.14.15. Permite que un invitado KVM malicioso bloquee el host, cuando éste es ejecutado en Power8, debido a un error de implementación de arch/powerpc/kvm/book3s_hv_rmhandlers.S en el manejo de los valores del registro SRR1

A denial of service problem was found in the Linux kernel's Kernel-based Virtual Machine (KVM) specific to PowerPC. In this flaw, a user with local access can confuse the host offline code, causing the guest to crash.

*Credits: N/A

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-10-28 CVE Reserved
2021-10-28 CVE Published
2023-03-08 EPSS Updated
2024-08-04 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-252: Unchecked Return Value

CAPEC

References (9)

URL	Tag	Source
https://lore.kernel.org/linuxppc-dev/87pmrtbbdt.fsf%40mpe.ellerman.id.au/T/#u	X_refsource_misc

URL	Date	SRC

URL	Date	SRC
http://www.openwall.com/lists/oss-security/2021/10/28/1	2023-11-07
https://git.kernel.org/linus/cdeb5d7d890e14f3b70e8087e745c4a6a7d9f337	2023-11-07

URL	Date	SRC
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.14.15	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AA7EAPPKWG4LMTQQLNNSKATY6ST2KQFE	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BBM4FP3IT3JZ2O7EBS7TEOG657N4ZGRE	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RRAIS3PG4EV5WFLYESR6FXWM4BJJGWVA	2023-11-07
https://access.redhat.com/security/cve/CVE-2021-43056	2022-05-10
https://bugzilla.redhat.com/show_bug.cgi?id=2017073	2022-05-10

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"				>= 5.2 < 5.4.15 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.2 < 5.4.15"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				33 Search vendor "Fedoraproject" for product "Fedora" and version "33"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				34 Search vendor "Fedoraproject" for product "Fedora" and version "34"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				35 Search vendor "Fedoraproject" for product "Fedora" and version "35"		-		Affected