CVE-2021-1644
Status: ModifiedHigh (7.8)—
HEVC Video Extensions Remote Code Execution Vulnerability
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Base score: 7.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 3.84%
- Percentile among all scored CVEs: 90
- Score date: 10/6/2026
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 (1)
CWEs
- NVD-CWE-noinfo
References
Raw JSON (NVD)
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{
"id": "CVE-2021-1644",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 9.3,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:M/Au:N/C:C/I:C/A:C",
"authentication": "NONE",
"integrityImpact": "COMPLETE",
"accessComplexity": "MEDIUM",
"availabilityImpact": "COMPLETE",
"confidentialityImpact": "COMPLETE"
},
"acInsufInfo": false,
"impactScore": 10,
"baseSeverity": "HIGH",
"obtainAllPrivilege": false,
"exploitabilityScore": 8.6,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": true
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "secure@microsoft.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.8,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.8
},
{
"type": "Secondary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.8,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.8
}
]
},
"affected": [
{
"source": "secure@microsoft.com",
"affectedData": [
{
"cpes": [
"cpe:2.3:a:microsoft:hevc_video_extensions:*:*:*:*:*:*:*:*"
],
"vendor": "Microsoft",
"product": "HEVC Video Extensions",
"versions": [
{
"status": "affected",
"version": "N/A"
}
],
"platforms": [
"Unknown"
]
}
]
}
],
"published": "2021-01-12T20:15:30.540",
"references": [
{
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-1644",
"source": "secure@microsoft.com"
},
{
"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1644",
"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": "HEVC Video Extensions Remote Code Execution Vulnerability"
},
{
"lang": "es",
"value": "Una Vulnerabilidad de Ejecución de Código Remota de HEVC Video Extensions. Este ID de CVE es diferente de CVE-2021-1643"
}
],
"lastModified": "2026-06-17T03:32:13.567",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:microsoft:hevc_video_extensions:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C3F3BD2E-D5D5-418A-BA67-CC2D75E19D94",
"versionEndExcluding": "1.0.33242.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "secure@microsoft.com"
}