Microsoft Windows Hyper-V NT Kernel Integration VSP Heap-based Buffer Overflow Vulnerability
Microsoft — Windows 10 Version 21H2
Windows Hyper-V NT Kernel Integration VSP Elevation of Privilege Vulnerability
7.8
9.8%
Vector breakdown
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
- Published
- Jan 14, 2025
- Modified
- Jun 9, 2026
- Added to KEV
- Jan 14, 2025
- Federal patch due
- Feb 4, 2025
CISA required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Weakness classification
Proof-of-concept & exploitation references
Weaponization
Public repositories whose name or description references CVE-2025-21333, found via a live GitHub search at request time. These are community-sourced signals, not a verified working exploit - cross-check each one before relying on it, and treat higher star counts and recent activity as (weak) corroboration, not proof.
No public GitHub repositories referencing CVE-2025-21333 were found at last check. Absence here is not proof no exploit exists - see the references below for vendor advisories and write-ups.
References
Frequently asked questions
What is CVE-2025-21333?
Windows Hyper-V NT Kernel Integration VSP Elevation of Privilege Vulnerability
How severe is CVE-2025-21333?
CVE-2025-21333 has a CVSS base score of 7.8 out of 10 (CVSS 3.1).
Is CVE-2025-21333 actively exploited in the wild?
Yes. CVE-2025-21333 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added Jan 14, 2025, meaning CISA has confirmed evidence of active exploitation.
What is the EPSS score for CVE-2025-21333?
9.8% - meaning FIRST.org's EPSS model estimates a 9.8% probability this vulnerability will be exploited in the wild within 30 days (95% percentile among all scored CVEs).
What type of vulnerability is CVE-2025-21333?
CVE-2025-21333 is classified under CWE-122 (CWE-122: Heap-based Buffer Overflow).
Cross-checked against
Impactr finds and proves whether CVE-2025-21333 - or flaws like it - are actually reachable in your own web apps and APIs, with a reproducible exploit as evidence.
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