CVE-2021-1691

Windows Hyper-V Denial of Service Vulnerability

View on CVE.org

Published Jan 12, 2021 CVSS 3.1 · 7.7 High EPSS 4.1% KEV · Not listed

Description

Windows Hyper-V Denial of Service Vulnerability

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Microsoft

Windows Server version 20H2

affected

Version	Status	Constraints
`10.0.0`	affected	< publication

Microsoft

Windows 10 Version 1909

affected

Version	Status	Constraints
`10.0.0`	affected	< publication

Microsoft

Windows Server, version 1909 (Server Core installation)

affected

Version	Status	Constraints
`10.0.0`	affected	< publication

Microsoft

Windows 10 Version 2004

affected

Version	Status	Constraints
`10.0.0`	affected	< publication

Microsoft

Windows Server version 2004

affected

Version	Status	Constraints
`10.0.0`	affected	< publication

Configuration 1 [-]

OR	cpe:2.3:o:microsoft:windows_10:20h2:::::::*
	cpe:2.3:o:microsoft:windows_10:1909:::::::*
	cpe:2.3:o:microsoft:windows_10:2004:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:20h2:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:1909:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:2004:::::::*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2021-7158	Windows Hyper-V Denial of Service Vulnerability

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Changed

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication Single

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

Exploit prediction score: 4.1% (4.069% probability within 30 days)

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-1691
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1691

History

Nov 22, 2024 12:00 PM Added references View changes

Type	Values Removed	Values Added
References		https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1691

Nov 19, 2024 4:15 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Oct 8, 2024 5:45 PM References updated View changes

Type	Values Removed	Values Added
References	https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1691

Oct 8, 2024 4:30 PM Added references View changes

Type	Values Removed	Values Added
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-1691

Subscriptions

Microsoft Windows 10 Windows 10 1809 Windows 10 1909 Windows Server 1909 Windows Server 2004 Windows Server 2016 Windows Server 20h2

Weaknesses

NVD-CWE-noinfo

Sources

CVE record Updated: Nov 19, 2024, 3:20 PM

Status: PUBLISHED
Assigner: microsoft
Published: Jan 12, 2021, 7:42 PM
Updated: Nov 19, 2024, 3:20 PM
Reserved: Dec 2, 2020, 12:00 AM

View source JSON

Vulnrichment Updated: Aug 3, 2024, 4:18 PM

Updated: Aug 3, 2024, 4:18 PM

NVD Updated: Jun 17, 2026, 3:32 AM

Status: Modified
Published: Jan 12, 2021, 8:15 PM
Modified: Jun 17, 2026, 3:32 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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Este ID de CVE es diferente de CVE-2021-1692"}], "id": "CVE-2021-1691", "lastModified": "2026-06-17T03:32:20.863", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "MEDIUM", "cvssData": {"accessComplexity": "LOW", "accessVector": "NETWORK", "authentication": "SINGLE", "availabilityImpact": "PARTIAL", "baseScore": 4.0, "confidentialityImpact": "NONE", "integrityImpact": "NONE", "vectorString": "AV:N/AC:L/Au:S/C:N/I:N/A:P", "version": "2.0"}, "exploitabilityScore": 8.0, "impactScore": 2.9, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.7, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.1, "impactScore": 4.0, "source": "secure@microsoft.com", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.7, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.1, "impactScore": 4.0, "source": "nvd@nist.gov", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2021-1691", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2024-01-10T16:58:17.409213Z", "version": "2.0.3"}}]}, "published": "2021-01-12T20:15:33.353", "references": [{"source": "secure@microsoft.com", "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-1691"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1691"}], "sourceIdentifier": "secure@microsoft.com", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}