How severe is CVE-2020-0909?

CVE-2020-0909 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-0909 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-0909?

CVE-2020-0909 primarily affects Microsoft Windows 10. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-0909?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-0909 published?

CVE-2020-0909 was published on 2020-05-21 and last updated on 2026-06-17.

CVE-2020-0909

CVE-2020-0909 is a high-severity vulnerability in Microsoft Windows 10 with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Windows 10
Published: 2020-05-21
Last modified: 2026-06-17

Description

A denial of service vulnerability exists when Hyper-V on a Windows Server fails to properly handle specially crafted network packets.To exploit the vulnerability, an attacker would send specially crafted network packets to the Hyper-V Server.The security update addresses the vulnerability by resolving the conditions where Hyper-V would fail to properly handle these network packets., aka 'Windows Hyper-V Denial of Service Vulnerability'.

Frequently asked questions

What is CVE-2020-0909?: A denial of service vulnerability exists when Hyper-V on a Windows Server fails to properly handle specially crafted network packets.To exploit the vulnerability, an attacker would send specially crafted network packets to the Hyper-V Server.The security update addresses the vulnerability by resolving the conditions where Hyper-V would fail to properly handle these network packets., aka 'Windows Hyper-V Denial of Service Vulnerability'.
How severe is CVE-2020-0909?: CVE-2020-0909 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-0909 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-0909?: CVE-2020-0909 primarily affects Microsoft Windows 10. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-0909?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-0909 published?: CVE-2020-0909 was published on 2020-05-21 and last updated on 2026-06-17.

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0909

Affected products (18)

cpe:2.3:o:microsoft:windows_10:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1607:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1709:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1803:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1809:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1903:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1909:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:1803:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:1903:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:1909:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*

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