Main Vulnerability Database Vulnerabilities #VU102617

Heap-based buffer overflow in Microsoft Windows and Windows Server - CVE-2025-21333

Published: January 14, 2025 / Updated: May 22, 2026

Vulnerability identifier: #VU102617

CSH Severity: High

CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2025-21333

CWE-ID: CWE-122

Exploitation vector: Local access

Exploit availability: The vulnerability is being exploited in the wild

Vulnerability details

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error in Windows Hyper-V NT Kernel Integration VSP component. A local user can trigger a heap-based buffer overflow and execute arbitrary code with SYSTEM privileges.

Note, the vulnerability is being actively exploited in the wild.

Affected software

Microsoft Windows
Windows Server

How to mitigate CVE-2025-21333

Install updates from vendor's website.

Microsoft Windows - addressed in versions 10 21H2 10.0.19044.5371, 10 22H2 10.0.19045.5371, 11 22H2 10.0.22621.4751, 11 23H2 10.0.22631.4751, 11 24H2 10.0.26100.3107
Windows Server - addressed in versions 2016 10.0.14393.7785, 2022 23H2 10.0.25398.1369, 2025 10.0.26100.2894

Links to Public Exploits and PoC-codes

External References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2025-21333

Related Security Bulletins

Multiple privilege escalation vulnerabilities in Microsoft Windows Hyper-V NT Kernel Integration VSP