CVE-2026-56179: CWE-346: Origin Validation Error in Microsoft Windows 11 Version 24H2
Origin validation error in Windows Network Address Translation (NAT) allows an unauthorized attacker to perform spoofing over an adjacent network.
AI Analysis
Technical Summary
This vulnerability, tracked as CVE-2026-56179 and categorized under CWE-346 (Origin Validation Error), affects Windows 11 Version 24H2 (build 10.0.26100.0). The flaw exists in the Windows NAT implementation, where improper origin validation enables an attacker on a network adjacent to the victim to spoof network traffic. The CVSS v3.1 base score is 8.3, indicating high severity with high impact on confidentiality, integrity, and availability. Microsoft has released an official fix to remediate this vulnerability.
Potential Impact
Successful exploitation allows an attacker without privileges and without user interaction to spoof network traffic over an adjacent network, potentially leading to full compromise of confidentiality, integrity, and availability of affected systems.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56179 to remediate this vulnerability.
CVE-2026-56179: CWE-346: Origin Validation Error in Microsoft Windows 11 Version 24H2
Description
Origin validation error in Windows Network Address Translation (NAT) allows an unauthorized attacker to perform spoofing over an adjacent network.
CVSS v3.1
Score 8.3high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, tracked as CVE-2026-56179 and categorized under CWE-346 (Origin Validation Error), affects Windows 11 Version 24H2 (build 10.0.26100.0). The flaw exists in the Windows NAT implementation, where improper origin validation enables an attacker on a network adjacent to the victim to spoof network traffic. The CVSS v3.1 base score is 8.3, indicating high severity with high impact on confidentiality, integrity, and availability. Microsoft has released an official fix to remediate this vulnerability.
Potential Impact
Successful exploitation allows an attacker without privileges and without user interaction to spoof network traffic over an adjacent network, potentially leading to full compromise of confidentiality, integrity, and availability of affected systems.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56179 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-06-19T13:53:31.990Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56179","vendor":"Microsoft"}]
Threat ID: 6a7b57f9bf8831d5391556d8
Added to database: 08/11/2026, 17:12:25 UTC
Last enriched: 08/11/2026, 23:12:39 UTC
Last updated: 08/12/2026, 00:12:09 UTC
Views: 5
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