CVE-2020-0904 — Windows Hyper-V Denial of Service Vulnerability

Executive Summary

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. 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. The security update addresses the vulnerability by resolving the conditions where Hyper-V would fail to handle these requests.

Overview

6.5

CVSS MEDIUM

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Denial of Service

Released Sep 8 2020

Last Updated Sep 8 2020

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.01235 — 0.65134 percentile

NVD CVSS 6.5 MEDIUM — matches MSRC

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:P/RL:O/RC:C

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

Low

USER INTERACTION

None

SCOPE

Changed

CONFIDENTIALITY

None

INTEGRITY

None

AVAILABILITY

High

EXPLOIT CODE MATURITY

Proof-of-Concept

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 5.9

EPSS Score

0.01235

probability of exploitation in the next 30 days

0.65134 percentile - updated 2026-06-21

View on FIRST.org

Affected Products

27 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows 10 Version 1607 for 32-bit Systems	`4577015 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1607 for x64-based Systems	`4577015 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for 32-bit Systems	`4577041 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for ARM64-based Systems	`4577041 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for x64-based Systems	`4577041 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for 32-bit Systems	`4577032 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for ARM64-based Systems	`4577032 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for x64-based Systems	`4577032 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for 32-bit Systems	`4570333 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for ARM64-based Systems	`4570333 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for x64-based Systems	`4570333 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for 32-bit Systems	`4574727 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for ARM64-based Systems	`4574727 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for x64-based Systems	`4574727 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for 32-bit Systems	`4574727 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for ARM64-based Systems	`4574727 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for x64-based Systems	`4574727 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 2004 for 32-bit Systems	`4571756 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 2004 for ARM64-based Systems	`4571756 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 2004 for x64-based Systems	`4571756 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2016	`4577015 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2016 (Server Core installation)	`4577015 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2019	`4570333 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2019 (Server Core installation)	`4570333 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 1903 (Server Core installation)	`4574727 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 1909 (Server Core installation)	`4574727 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 2004 (Server Core installation)	`4571756 (Security Update)`	Important	Denial of Service	Yes

Patches

6 patches

Article	Type	Restart
`4577015`	Security Update	Yes
`4577041`	Security Update	Yes
`4577032`	Security Update	Yes
`4570333`	Security Update	Yes
`4574727`	Security Update	Yes
`4571756`	Security Update	Yes

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

Daniel Fernandez Kuehr

References

MSRC Advisory MITRE NVD