Is CVE-2025-21335 actively exploited?

Yes. CVE-2025-21335 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, which means exploitation in the wild has been confirmed.

Can CVE-2025-21335 be exploited remotely?

The attack vector of CVE-2025-21335 has not been classified yet.

What is the CVSS score of CVE-2025-21335?

CVE-2025-21335 has not received a CVSS score yet.

HOME VULNERABILITIESCVE-2025-21335

HIGHCISA KEVIN THE WILD

CVE-2025-21335

Published: January 14, 2025

EPSS:9.89%probability of exploitation in 30 daysPercentile:92.9th

Official Description

Microsoft Windows Hyper-V NT Kernel Integration VSP contains a use-after-free vulnerability that allows a local attacker to gain SYSTEM privileges.

NVD Source

CISA KEV Advisory

Microsoft Windows Hyper-V NT Kernel Integration VSP Use-After-Free Vulnerability

Microsoft Windows Hyper-V NT Kernel Integration VSP contains a use-after-free vulnerability that allows a local attacker to gain SYSTEM privileges.

Added to KEV: 2025-01-14Federal patch deadline: 2025-02-04

Required Action (CISA)

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Risk Analysis

Microsoft Windows Hyper-V NT Kernel Integration VSP contains a use-after-free vulnerability that allows a local attacker to gain SYSTEM privileges. This is a high-severity flaw with a significant exploitation probability (EPSS 0.09894), indicating a strong likelihood of exploitation. This vulnerability is confirmed to be actively exploited by CISA.

This vulnerability is being actively exploited in the wild. Exploitation requires local access to the affected system.

Recommended Action

Apply all available security updates for Microsoft Windows Hyper-V. Restrict local access to Hyper-V hosts and implement least privilege principles.

Generated by the CTIWATCH analysis pipeline from this CVE's metadata (CVSS, EPSS, KEV status, exploit intelligence). Verify against vendor advisories before acting.

Technical Analysis

CVE-2025-21335 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

CISA has added CVE-2025-21335 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.