CVE-2025-21333
Microsoft Windows Hyper-V NT Kernel Integration VSP Heap-based Buffer Overflow Vulnerability
Microsoft WindowsOperating systems
CVSS
7.8HighExploit odds (EPSS)10.1%Chance of exploitation activity in the next 30 days, higher than 95% of CVEs. Scored 23 Oct 2026FIRST EPSS
CISA required actionApply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. CISA KEV
What fixes it
- 10.0.19044.5371Windows 10 Version 21H2CVE List
- 10.0.19045.5371Windows 10 Version 22H2CVE List
- 10.0.22621.4751Windows 11 version 22H2CVE List
- 10.0.22631.4751Windows 11 version 22H3CVE List
- 10.0.22631.4751Windows 11 Version 23H2CVE List
- 10.0.26100.2894Windows 11 Version 24H2CVE List
Show all 9 fixed versions
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Timeline
- 14 Jan 2025Added to CISA KEVCISA KEV
- 14 Jan 2025, 18:04 UTCPublishedCVE List
- 16 Sep 2025Exploit code publicExploit-DB
Public exploit code and templates 1
- Local exploitMicrosoft Windows Server 2025 Hyper-V NT Kernel Integration VSP - Elevation of Privilege 16 Sep 2025Exploit-DB
Listed so defenders can prioritize. Threatline links to the source and does not host exploit code.
Description
Microsoft Windows Hyper-V NT Kernel Integration VSP contains a heap-based buffer overflow vulnerability that allows a local attacker to gain SYSTEM privileges.
Text from CVE List
Affected versions 9
- Windows 10 Version 21H2affected: 10.0.19044.0 before 10.0.19044.5371CVE List
- Windows 10 Version 22H2affected: 10.0.19045.0 before 10.0.19045.5371CVE List
- Windows 11 version 22H2affected: 10.0.22621.0 before 10.0.22621.4751CVE List
- Windows 11 version 22H3affected: 10.0.22631.0 before 10.0.22631.4751CVE List
- Windows 11 Version 23H2affected: 10.0.22631.0 before 10.0.22631.4751CVE List
- Windows 11 Version 24H2affected: 10.0.26100.0 before 10.0.26100.2894CVE List
- Windows Server 2022, 23H2 Edition (Server Core installation)affected: 10.0.25398.0 before 10.0.25398.1369CVE List
- Windows Server 2025affected: 10.0.26100.0 before 10.0.26100.2894CVE List
- Windows Server 2025 (Server Core installation)affected: 10.0.26100.0 before 10.0.26100.2894CVE List
References 7
- msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21333Fixvia CVE List
- exploit-db.com/exploits/52436Exploitvia CVE List
- msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-21333Referencevia CISA KEV
- nvd.nist.gov/vuln/detail/CVE-2025-21333Referencevia CISA KEV
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21333Referencevia CVE List
- vicarius.io/vsociety/posts/cve-2025-21333-elevated-privilege-exposure-in-windows-hyper-v-by-microsoft-mitigation-scriptReferencevia CVE List
- vicarius.io/vsociety/posts/cve-2025-21333-elevated-privilege-exposure-in-windows-hyper-v-by-microsoft-detection-scriptReferencevia CVE List