MSRC_CVE-2026-56181

Vulnerability from csaf_microsoft - Published: 2026-07-14 07:00 - Updated: 2026-07-14 07:00
Summary
Windows Network Address Translation (NAT) Spoofing Vulnerability
Severity
Moderate
Notes
Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
Customer Action: Required. The vulnerability documented by this CVE requires customer action to resolve.
CWE-346 - Origin Validation Error
Affected products
Product Identifier Version Remediation
Windows 11 Version 24H2 for ARM64-based Systems 10.0.26100.8875
Windows 11 Version 24H2 for ARM64-based Systems
10.0.26100.8875
Windows 11 Version 24H2 for x64-based Systems 10.0.26100.8875
Windows 11 Version 24H2 for x64-based Systems
10.0.26100.8875
Windows Server 2025 10.0.26100.33158
Windows Server 2025
10.0.26100.33158
Windows Server 2025 (Server Core installation) 10.0.26100.33158
Windows Server 2025 (Server Core installation)
10.0.26100.33158
Windows 11 Version 25H2 for ARM64-based Systems 10.0.26100.8875
Windows 11 Version 25H2 for ARM64-based Systems
10.0.26100.8875
Windows 11 Version 25H2 for x64-based Systems 10.0.26100.8875
Windows 11 Version 25H2 for x64-based Systems
10.0.26100.8875
Windows 11 version 26H1 for x64-based Systems 10.0.28000.2525
Windows 11 version 26H1 for x64-based Systems
10.0.28000.2525
Windows 11 Version 26H1 for ARM64-based Systems 10.0.28000.2525
Windows 11 Version 26H1 for ARM64-based Systems
10.0.28000.2525
Product Identifier Version Remediation
Windows 11 Version 26H1 for ARM64-based Systems <10.0.28000.2525
Windows 11 Version 26H1 for ARM64-based Systems
<10.0.28000.2525
Vendor Fix fix
Windows 11 version 26H1 for x64-based Systems <10.0.28000.2525
Windows 11 version 26H1 for x64-based Systems
<10.0.28000.2525
Vendor Fix fix
Windows 11 Version 25H2 for x64-based Systems <10.0.26100.8875
Windows 11 Version 25H2 for x64-based Systems
<10.0.26100.8875
Vendor Fix fix
Windows 11 Version 25H2 for ARM64-based Systems <10.0.26100.8875
Windows 11 Version 25H2 for ARM64-based Systems
<10.0.26100.8875
Vendor Fix fix
Windows Server 2025 (Server Core installation) <10.0.26100.33158
Windows Server 2025 (Server Core installation)
<10.0.26100.33158
Vendor Fix fix
Windows Server 2025 <10.0.26100.33158
Windows Server 2025
<10.0.26100.33158
Vendor Fix fix
Windows 11 Version 24H2 for x64-based Systems <10.0.26100.8875
Windows 11 Version 24H2 for x64-based Systems
<10.0.26100.8875
Vendor Fix fix
Windows 11 Version 24H2 for ARM64-based Systems <10.0.26100.8875
Windows 11 Version 24H2 for ARM64-based Systems
<10.0.26100.8875
Vendor Fix fix
Threats
Impact Spoofing
Exploit Status Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely
Acknowledgments
Malcolm Stagg with <a href="https://www.sodium24.com/">SODIUM-24, LLC</a>

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          "title": "Assigning CNA"
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          "title": "According to the CVSS metric, the attack vector is adjacent (AV:A). What does that mean for this vulnerability?"
        },
        {
          "category": "faq",
          "text": "The attacker must inject themselves into the logical network path between the target and the resource requested by the victim to read or modify network communications. This is called a machine-in-the-middle (MITM) attack.",
          "title": "According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?"
        }
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      "scores": [
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          "cvss_v3": {
            "attackComplexity": "HIGH",
            "attackVector": "ADJACENT_NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8.3,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "environmentalScore": 0.0,
            "exploitCodeMaturity": "UNPROVEN",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "remediationLevel": "OFFICIAL_FIX",
            "reportConfidence": "CONFIRMED",
            "scope": "CHANGED",
            "temporalScore": 7.2,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
          },
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            "2",
            "3",
            "4",
            "5",
            "6",
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            "8"
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      "threats": [
        {
          "category": "impact",
          "details": "Spoofing"
        },
        {
          "category": "exploit_status",
          "details": "Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely"
        }
      ],
      "title": "Windows Network Address Translation (NAT) Spoofing Vulnerability"
    }
  ]
}



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Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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