CVE-2020-1118
Status: ModifiedHigh (7.5)—
A denial of service vulnerability exists in the Windows implementation of Transport Layer Security (TLS) when it improperly handles certain key exchanges. An attacker who successfully exploited the vulnerability could cause a target system to stop responding. To exploit this vulnerability, a remote unauthenticated attacker could send a specially crafted request to a target system utilizing TLS 1.2 or lower, triggering the system to automatically reboot. The update addresses the vulnerability by changing the way TLS key exchange messages are validated.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Base score: 7.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 15%
- Percentile among all scored CVEs: 97
- Score date: 10/19/2026
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 (2)
CWEs
- NVD-CWE-Other
References
Raw JSON (NVD)
Show
{
"id": "CVE-2020-1118",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 7.8,
"accessVector": "NETWORK",
"vectorString": "AV:N/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": "HIGH",
"obtainAllPrivilege": false,
"exploitabilityScore": 10,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"type": "Primary",
"source": "secure@microsoft.com",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 8.6,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 4,
"exploitabilityScore": 3.9
},
{
"type": "Secondary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "secure@microsoft.com",
"affectedData": [
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1709",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"ARM64-based Systems",
"x64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1709 for 32-bit Systems",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"32-bit Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1803",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"32-bit Systems",
"ARM64-based Systems",
"x64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1809",
"versions": [
{
"status": "affected",
"version": "10.0.17763.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"32-bit Systems",
"x64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1809",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"ARM64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1903 for 32-bit Systems",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
]
},
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1903 for ARM64-based Systems",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
]
},
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1903 for x64-based Systems",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
]
},
{
"vendor": "Microsoft",
"product": "Windows 10 Version 1909",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"32-bit Systems",
"ARM64-based Systems",
"x64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows Server 2019",
"versions": [
{
"status": "affected",
"version": "10.0.17763.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"x64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows Server 2019 (Server Core installation)",
"versions": [
{
"status": "affected",
"version": "10.0.17763.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"x64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows Server, version 1803 (Server Core Installation)",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"x64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows Server, version 1903 (Server Core installation)",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"x64-based Systems"
]
},
{
"vendor": "Microsoft",
"product": "Windows Server, version 1909 (Server Core installation)",
"versions": [
{
"status": "affected",
"version": "10.0.0",
"lessThan": "publication",
"versionType": "custom"
}
],
"platforms": [
"x64-based Systems"
]
}
]
}
],
"published": "2020-05-21T23:15:15.460",
"references": [
{
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-1118",
"source": "secure@microsoft.com"
},
{
"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1118",
"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-Other"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A denial of service vulnerability exists in the Windows implementation of Transport Layer Security (TLS) when it improperly handles certain key exchanges. An attacker who successfully exploited the vulnerability could cause a target system to stop responding.\nTo exploit this vulnerability, a remote unauthenticated attacker could send a specially crafted request to a target system utilizing TLS 1.2 or lower, triggering the system to automatically reboot.\nThe update addresses the vulnerability by changing the way TLS key exchange messages are validated."
},
{
"lang": "es",
"value": "Se presenta una vulnerabilidad denegación de servicio en la implementación de Windows de Transport Layer Security (TLS) cuando maneja inapropiadamente determinados intercambios de claves, también se conoce como \"Microsoft Windows Transport Layer Security Denial of Service Vulnerability\"."
}
],
"lastModified": "2026-08-19T17:17:20.220",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:microsoft:windows_10:1709:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "83B14968-3985-43C3-ACE5-8307196EFAE3"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_10:1803:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "7CB85C75-4D35-480E-843D-60579EC75FCB"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_10:1809:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "6B8F3DD2-A145-4AF1-8545-CC42892DA3D1"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_10:1903:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "3FB5CDAE-C713-4D9D-9D6A-2C2E8924A4BB"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_10:1909:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "E9273B95-20ED-4547-B0A8-95AD15B30372"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "DB79EE26-FC32-417D-A49C-A1A63165A968"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_server_2019:1903:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "587088E1-75CC-43A5-A3E3-83D1AA2F10D3"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_server_2019:1909:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "9C5D9764-AD4B-4F86-BDAB-188896D9D02B"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "secure@microsoft.com"
}