How severe is CVE-2025-26647?

CVE-2025-26647 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-26647 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-26647?

CVE-2025-26647 primarily affects Microsoft Windows Server 2008. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-26647?

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-2025-26647 have an EU (EUVD) identifier?

Yes. CVE-2025-26647 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-10222.

When was CVE-2025-26647 published?

CVE-2025-26647 was published on 2025-04-08 and last updated on 2026-06-17.

CVE-2025-26647

CVE-2025-26647 is a high-severity vulnerability in Microsoft Windows Server 2008 with a CVSS 3.x base score of 8.8. 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 8.8)
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-10222
Weakness: CWE-20
Affected product: Microsoft Windows Server 2008
Published: 2025-04-08
Last modified: 2026-06-17

Description

Improper input validation in Windows Kerberos allows an authorized attacker to elevate privileges over a network.

Frequently asked questions

What is CVE-2025-26647?: Improper input validation in Windows Kerberos allows an authorized attacker to elevate privileges over a network.
How severe is CVE-2025-26647?: CVE-2025-26647 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-26647 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-26647?: CVE-2025-26647 primarily affects Microsoft Windows Server 2008. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-26647?: 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-2025-26647 have an EU (EUVD) identifier?: Yes. CVE-2025-26647 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-10222.
When was CVE-2025-26647 published?: CVE-2025-26647 was published on 2025-04-08 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-26647

Affected products (10)

cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:x86:*
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_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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