CVE-2020-1243
Status: ModifiedHigh (7.8)—
<p>A denial of service vulnerability exists when Microsoft Hyper-V on a host server fails to properly validate specific malicious data from a user on a guest operating system.</p> <p>To exploit the vulnerability, an attacker who already has a privileged account on a guest operating system, running as a virtual machine, could run a specially crafted application.</p> <p>The security update addresses the vulnerability by resolving the conditions where Hyper-V would fail to handle these requests.</p>
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Base score: 7.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.90%
- Percentile among all scored CVEs: 59
- Score date: 10/16/2026
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 (3)
CWEs
- NVD-CWE-noinfo
References
Raw JSON (NVD)
Show
{
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"published": "2020-10-16T23:15:17.680",
"references": [
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"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1243",
"tags": [
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"source": "secure@microsoft.com"
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"value": "<p>A denial of service vulnerability exists when Microsoft Hyper-V on a host server fails to properly validate specific malicious data from a user on a guest operating system.</p>\n<p>To exploit the vulnerability, an attacker who already has a privileged account on a guest operating system, running as a virtual machine, could run a specially crafted application.</p>\n<p>The security update addresses the vulnerability by resolving the conditions where Hyper-V would fail to handle these requests.</p>"
},
{
"lang": "es",
"value": "Se presenta una vulnerabilidad de denegación de servicio cuando Microsoft Hyper-V en un servidor host presenta un fallo al comprobar apropiadamente datos maliciosos específicos de un usuario en un sistema operativo invitado. Para explotar la vulnerabilidad, un atacante que ya presenta una cuenta privilegiada en un sistema operativo invitado, ejecutándose como una máquina virtual, podría correr una aplicación especialmente diseñada. La actualización de seguridad aborda la vulnerabilidad al resolver las condiciones en las que Hyper-V no podría manejar estas peticiones, también se conoce como \"Windows Hyper-V Denial of Service Vulnerability\""
}
],
"lastModified": "2026-06-17T03:00:53.447",
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