CVE-2021-46977

In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Disable preemption when probing user return MSRs Disable preemption when probing a user return MSR via RDSMR/WRMSR. If the MSR holds a different value per logical CPU, the WRMSR could corrupt the host's value if KVM is preempted between the RDMSR and WRMSR, and then rescheduled on a different CPU. Opportunistically land the helper in common x86, SVM will use the helper in a future commit.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/31f29749ee970c251b3a7e5b914108425940d089	Patch
https://git.kernel.org/stable/c/5104d7ffcf24749939bea7fdb5378d186473f890	Patch
https://git.kernel.org/stable/c/5adcdeb57007ccf8ab7ac20bf787ffb6fafb1a94	Patch
https://git.kernel.org/stable/c/e3ea1895df719c4ef87862501bb10d95f4177bed	Patch
https://git.kernel.org/stable/c/31f29749ee970c251b3a7e5b914108425940d089	Patch
https://git.kernel.org/stable/c/5104d7ffcf24749939bea7fdb5378d186473f890	Patch
https://git.kernel.org/stable/c/5adcdeb57007ccf8ab7ac20bf787ffb6fafb1a94	Patch
https://git.kernel.org/stable/c/e3ea1895df719c4ef87862501bb10d95f4177bed	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:5.13:rc1::::::

History

No history.

Information

Published : 2024-02-28 09:15

Updated : 2025-01-08 17:34

NVD link : CVE-2021-46977

Mitre link : CVE-2021-46977

CVE.ORG link : CVE-2021-46977

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

{"id": "CVE-2021-46977", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2024-02-28T09:15:37.140", "references": [{"url": "https://git.kernel.org/stable/c/31f29749ee970c251b3a7e5b914108425940d089", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/5104d7ffcf24749939bea7fdb5378d186473f890", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/5adcdeb57007ccf8ab7ac20bf787ffb6fafb1a94", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e3ea1895df719c4ef87862501bb10d95f4177bed", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/31f29749ee970c251b3a7e5b914108425940d089", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/5104d7ffcf24749939bea7fdb5378d186473f890", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/5adcdeb57007ccf8ab7ac20bf787ffb6fafb1a94", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/e3ea1895df719c4ef87862501bb10d95f4177bed", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: VMX: Disable preemption when probing user return MSRs\n\nDisable preemption when probing a user return MSR via RDSMR/WRMSR. If\nthe MSR holds a different value per logical CPU, the WRMSR could corrupt\nthe host's value if KVM is preempted between the RDMSR and WRMSR, and\nthen rescheduled on a different CPU.\n\nOpportunistically land the helper in common x86, SVM will use the helper\nin a future commit."}, {"lang": "es", "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: KVM: VMX: deshabilite la preferencia al sondear los MSR devueltos por el usuario. Deshabilite la preferencia al sondear el MSR devuelto por un usuario a trav\u00e9s de RDSMR/WRMSR. Si MSR tiene un valor diferente por CPU l\u00f3gica, WRMSR podr\u00eda da\u00f1ar el valor del host si KVM se adelanta entre RDMSR y WRMSR y luego se reprograma en una CPU diferente. De manera oportunista, coloque el asistente en x86 com\u00fan, SVM usar\u00e1 el asistente en una confirmaci\u00f3n futura."}], "lastModified": "2025-01-08T17:34:32.217", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2BB4E5E8-4AAD-475A-A1B9-F287254C7D72", "versionEndExcluding": "5.10.38", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "83B53E9A-F426-4C03-9A5F-A931FF79827E", "versionEndExcluding": "5.11.22", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0274929A-B36C-4F4C-AB22-30A0DD6B995B", "versionEndExcluding": "5.12.5", "versionStartIncluding": "5.12"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0CBAD0FC-C281-4666-AB2F-F8E6E1165DF7"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}