CVE-2026-83903

Heap-based buffer overflow in Windows Direct Composition 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-2026-83903	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_11_26h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_26h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2025:::::::x64:*

History

29 Oct 2026, 18:20

Type	Values Removed	Values Added
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83903 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83903 - Vendor Advisory
CPE		cpe:2.3:o:microsoft:windows_11_26h2:::::::x64:* cpe:2.3:o:microsoft:windows_11_25h2:::::::arm64:* 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_26h2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_25h2:::::::x64:* cpe:2.3:o:microsoft:windows_server_2025:::::::x64:*
First Time		Microsoft windows 11 25h2 Microsoft Microsoft windows 11 26h2 Microsoft windows Server 2025 Microsoft windows 11 24h2

13 Oct 2026, 19:20

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 19:20

Updated : 2026-10-29 18:20

NVD link : CVE-2026-83903

Mitre link : CVE-2026-83903

CVE.ORG link : CVE-2026-83903

JSON object : View

Products Affected

microsoft

windows_11_25h2
windows_11_26h2
windows_11_24h2
windows_server_2025

CWE

CWE-122

Heap-based Buffer Overflow

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