How severe is CVE-2026-27928?

CVE-2026-27928 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-27928 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-27928?

CVE-2026-27928 primarily affects Microsoft Windows Server 2016. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-27928?

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.

Does CVE-2026-27928 have an EU (EUVD) identifier?

Yes. CVE-2026-27928 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22481.

When was CVE-2026-27928 published?

CVE-2026-27928 was published on 2026-04-14 and last updated on 2026-06-17.

CVE-2026-27928

CVE-2026-27928 is a high-severity vulnerability in Microsoft Windows Server 2016 with a CVSS 3.x base score of 8.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 8.7)
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22481
Weakness: CWE-20
Affected product: Microsoft Windows Server 2016
Published: 2026-04-14
Last modified: 2026-06-17

Description

Improper input validation in Windows Hello allows an unauthorized attacker to bypass a security feature over a network.

Frequently asked questions

What is CVE-2026-27928?: Improper input validation in Windows Hello allows an unauthorized attacker to bypass a security feature over a network.
How severe is CVE-2026-27928?: CVE-2026-27928 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-27928 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27928?: CVE-2026-27928 primarily affects Microsoft Windows Server 2016. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-27928?: 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.
Does CVE-2026-27928 have an EU (EUVD) identifier?: Yes. CVE-2026-27928 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22481.
When was CVE-2026-27928 published?: CVE-2026-27928 was published on 2026-04-14 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27928

Affected products (5)

cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*

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