How severe is CVE-2025-21225?

CVE-2025-21225 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-21225 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-21225?

CVE-2025-21225 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-2025-21225?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-21225 have an EU (EUVD) identifier?

Yes. CVE-2025-21225 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2292.

When was CVE-2025-21225 published?

CVE-2025-21225 was published on 2025-01-14 and last updated on 2026-06-17.

CVE-2025-21225

CVE-2025-21225 is a medium-severity vulnerability in Microsoft Windows Server 2016 with a CVSS 3.x base score of 5.9. 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-843.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-2292
Weakness: CWE-843
Affected product: Microsoft Windows Server 2016
Published: 2025-01-14
Last modified: 2026-06-17

Description

Windows Remote Desktop Gateway (RD Gateway) Denial of Service Vulnerability

Frequently asked questions

What is CVE-2025-21225?: Windows Remote Desktop Gateway (RD Gateway) Denial of Service Vulnerability
How severe is CVE-2025-21225?: CVE-2025-21225 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-21225 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21225?: CVE-2025-21225 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-2025-21225?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21225 have an EU (EUVD) identifier?: Yes. CVE-2025-21225 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2292.
When was CVE-2025-21225 published?: CVE-2025-21225 was published on 2025-01-14 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21225

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:*:*:*:*:*:*:x64:*

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