Microsoft Windows Hyper-V NT Kernel Integration VSP Heap-based Buffer Overflow Vulnerability

HIGH 7.8EXPLOITED (CISA KEV)CVE-2025-21333 · Published 14/01/2025 · updated 17/06/2026

Microsoft Windows Hyper-V NT Kernel Integration VSP Heap-based Buffer Overflow Vulnerability. Actively exploited: CISA added this vulnerability to its Known Exploited Vulnerabilities catalog on 14/01/2025. Patch affected systems as an emergency.

Package	Affected versions	Patched versions
Windows Microsoft	Versions not published yet (product named by CISA KEV)

Description

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

References

msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21333 · Patch
exploit-db.com/exploits/52436 · Exploit
vicarius.io/vsociety/posts/cve-2025-21333-elevated-privilege-exposure-in-windows-hyper-v-by-microsoft-detection-script · Mitigation
vicarius.io/vsociety/posts/cve-2025-21333-elevated-privilege-exposure-in-windows-hyper-v-by-microsoft-mitigation-script · Mitigation
cisa.gov/known-exploited-vulnerabilities-catalog · US Government Resource
CISA KEV · CVE-2025-21333

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