CVE-2026-21245

Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21245	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_11_24h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

No history.

Information

Published : 2026-02-10 18:16

Updated : 2026-02-11 20:44

NVD link : CVE-2026-21245

Mitre link : CVE-2026-21245

CVE.ORG link : CVE-2026-21245

JSON object : View

Products Affected

microsoft

windows_server_2025
windows_11_25h2
windows_11_24h2

CWE

CWE-122

Heap-based Buffer Overflow

CWE-787

Out-of-bounds Write

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