What is CVE-2020-16894?

A denial of service vulnerability exists when Windows Network Address Translation (NAT) on a host server fails to properly validate input from a privileged user on a guest operating system. An attacker who successfully exploited the vulnerability could cause the host server to crash. 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 that causes a host machine to crash. The update addresses the vulnerability by modifying how Windows NAT accesses the host.

How severe is CVE-2020-16894?

CVE-2020-16894 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-16894 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-16894?

CVE-2020-16894 primarily affects Microsoft Windows 10. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-16894?

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-2020-16894 published?

CVE-2020-16894 was published on 2020-10-16 and last updated on 2026-06-17.

CVE-2020-16894

CVE-2020-16894 is a high-severity vulnerability in Microsoft Windows 10 with a CVSS 3.x base score of 7.7. 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 7.7)
CVSS v2: 6.8
EPSS exploit prediction: 5% (90th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Windows 10
Published: 2020-10-16
Last modified: 2026-06-17

Description

A denial of service vulnerability exists when Windows Network Address Translation (NAT) on a host server fails to properly validate input from a privileged user on a guest operating system. An attacker who successfully exploited the vulnerability could cause the host server to crash. 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 that causes a host machine to crash. The update addresses the vulnerability by modifying how Windows NAT accesses the host.

Frequently asked questions

What is CVE-2020-16894?: A denial of service vulnerability exists when Windows Network Address Translation (NAT) on a host server fails to properly validate input from a privileged user on a guest operating system. An attacker who successfully exploited the vulnerability could cause the host server to crash. 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 that causes a host machine to crash. The update addresses the vulnerability by modifying how Windows NAT accesses the host.
How severe is CVE-2020-16894?: CVE-2020-16894 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-16894 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-16894?: CVE-2020-16894 primarily affects Microsoft Windows 10. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-16894?: 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-2020-16894 published?: CVE-2020-16894 was published on 2020-10-16 and last updated on 2026-06-17.

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16894

Affected products (2)

cpe:2.3:o:microsoft:windows_10:1607:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*

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