CVE-2021-43246
Status: ModifiedMedium (5.6)—
Windows Hyper-V Denial of Service Vulnerability
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H
- Base score: 5.6
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.77%
- Percentile among all scored CVEs: 55
- Score date: 10/15/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (4)
CWEs
- NVD-CWE-noinfo
References
Raw JSON (NVD)
Show
{
"id": "CVE-2021-43246",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 4.9,
"accessVector": "LOCAL",
"vectorString": "AV:L/AC:L/Au:N/C:N/I:N/A:C",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
"availabilityImpact": "COMPLETE",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 6.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 3.9,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
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"cvssData": {
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"baseScore": 5.6,
"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
"impactScore": 4,
"exploitabilityScore": 1.1
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{
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"vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
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}
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"product": "Windows 10 Version 21H1",
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{
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"vendor": "Microsoft",
"product": "Windows Server 2022",
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{
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"product": "Windows 10 Version 2004",
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{
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"vendor": "Microsoft",
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"lessThan": "10.0.19041.1415",
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{
"cpes": [
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],
"vendor": "Microsoft",
"product": "Windows Server version 20H2",
"versions": [
{
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"version": "10.0.0",
"lessThan": "10.0.19042.1415",
"versionType": "custom"
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],
"platforms": [
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},
{
"cpes": [
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],
"vendor": "Microsoft",
"product": "Windows 11 version 21H2",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "10.0.22000.376",
"versionType": "custom"
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],
"platforms": [
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},
{
"cpes": [
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],
"vendor": "Microsoft",
"product": "Windows 10 Version 21H2",
"versions": [
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"version": "10.0.0",
"lessThan": "10.0.19044.1415",
"versionType": "custom"
}
],
"platforms": [
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}
]
}
],
"published": "2021-12-15T15:15:10.553",
"references": [
{
"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43246",
"tags": [
"Patch",
"Vendor Advisory"
],
"source": "secure@microsoft.com"
},
{
"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43246",
"tags": [
"Patch",
"Vendor Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Windows Hyper-V Denial of Service Vulnerability"
},
{
"lang": "es",
"value": "Una vulnerabilidad de Denegación de Servicio en Windows Hyper-V"
}
],
"lastModified": "2026-06-17T04:10:44.033",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
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"operator": "OR"
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"sourceIdentifier": "secure@microsoft.com"
}