CVE-2026-56181

Origin validation error in Windows Network Address Translation (NAT) allows an unauthorized attacker to perform spoofing over an adjacent network.

CVSS v3 8.3 HIGH

8.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 6.0

Attack Vector ADJACENT_NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56181	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_11_24h2::::::::
	cpe:2.3:o:microsoft:windows_11_25h2::::::::
	cpe:2.3:o:microsoft:windows_11_26h1::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

22 Jul 2026, 11:48

Type	Values Removed	Values Added
First Time		Microsoft windows 11 24h2 Microsoft windows Server 2025 Microsoft windows 11 25h2 Microsoft Microsoft windows 11 26h1
CPE		cpe:2.3:o:microsoft:windows_11_26h1:::::::: cpe:2.3:o:microsoft:windows_11_24h2:::::::: cpe:2.3:o:microsoft:windows_11_25h2:::::::: cpe:2.3:o:microsoft:windows_server_2025::::::::
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56181 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56181 - Patch, Vendor Advisory

14 Jul 2026, 18:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-14 18:18

Updated : 2026-07-22 16:18

NVD link : CVE-2026-56181

Mitre link : CVE-2026-56181

CVE.ORG link : CVE-2026-56181

JSON object : View

Products Affected

microsoft

windows_11_25h2
windows_11_24h2
windows_11_26h1
windows_server_2025

CWE

CWE-346

Origin Validation Error

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