CVE-2025-21335

HIGH CISA KEV

Published Jan 14, 2025 Modified Oct 27, 2025 CWE-416

Description

Windows Hyper-V NT Kernel Integration VSP Elevation of Privilege Vulnerability

CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CISA Known Exploited Vulnerability

This vulnerability is actively exploited in the wild.

Added: Jan 14, 2025 Remediation due: Feb 4, 2025

Weakness Type (CWE)

CWE-416 Use After Free

Affected Products

Vendor	Product	Versions
microsoft	windows_10_21h2	< 10.0.19044.5371
microsoft	windows_10_22h2	< 10.0.19045.5371
microsoft	windows_11_22h2	< 10.0.22621.4751
microsoft	windows_11_22h2	< 10.0.22621.4751
microsoft	windows_11_23h2	< 10.0.22631.4751
microsoft	windows_11_23h2	< 10.0.22631.4751
microsoft	windows_11_24h2	< 10.0.26100.2894
microsoft	windows_11_24h2	< 10.0.26100.2894
microsoft	windows_server_2022_23h2	< 10.0.25398.1369
microsoft	windows_server_2025	< 10.0.26100.2894

References

Advisories & Patches

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21335

Other References

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21335

Frequently Asked Questions

What is CVE-2025-21335? +

Windows Hyper-V NT Kernel Integration VSP Elevation of Privilege Vulnerability It has a CVSS v3.1 base score of 7.8 (HIGH). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

How severe is CVE-2025-21335? +

CVE-2025-21335 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-21335? +

CVE-2025-21335 affects products from microsoft, specifically: windows_10_21h2, windows_10_22h2, windows_11_22h2, windows_11_23h2, windows_11_24h2, windows_server_2022_23h2, windows_server_2025. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-21335? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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