How severe is CVE-2026-33826?

CVE-2026-33826 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-33826 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33826?

CVE-2026-33826 primarily affects Microsoft Windows Server 2012. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-33826?

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-2026-33826 have an EU (EUVD) identifier?

Yes. CVE-2026-33826 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22645.

When was CVE-2026-33826 published?

CVE-2026-33826 was published on 2026-04-14 and last updated on 2026-06-17.

CVE-2026-33826

CVE-2026-33826 is a high-severity vulnerability in Microsoft Windows Server 2012 with a CVSS 3.x base score of 8.0. 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 8.0)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22645
Weakness: CWE-20
Affected product: Microsoft Windows Server 2012
Published: 2026-04-14
Last modified: 2026-06-17

Description

Improper input validation in Windows Active Directory allows an authorized attacker to execute code over an adjacent network.

Frequently asked questions

What is CVE-2026-33826?: Improper input validation in Windows Active Directory allows an authorized attacker to execute code over an adjacent network.
How severe is CVE-2026-33826?: CVE-2026-33826 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-33826 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33826?: CVE-2026-33826 primarily affects Microsoft Windows Server 2012. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-33826?: 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-2026-33826 have an EU (EUVD) identifier?: Yes. CVE-2026-33826 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22645.
When was CVE-2026-33826 published?: CVE-2026-33826 was published on 2026-04-14 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33826

Affected products (6)

cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
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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