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TI-2026-40553 Aliases CVE-2026-56179GHSA-rxw5-jh43-59h9

Windows Network Address Translation (NAT) Spoofing Vulnerability

Priority LOW 38CWE-346Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Spoofing
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.

Summary

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00276 20th percentileScored 2026-11-07
Fix Fixed Microsoft: 5 updates

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftWindows 11 Version 24H210.0.26100.0 to before 10.0.26100.916810.0.26100.9168Patch availableCNA
MicrosoftWindows 11 Version 25H210.0.26200.0 to before 10.0.26200.916810.0.26200.9168Patch availableCNA
MicrosoftWindows 11 version 26H110.0.28000.0 to before 10.0.28000.270410.0.28000.2704Patch availableCNA
MicrosoftWindows Server 202510.0.26100.0 to before 10.0.26100.3329610.0.26100.33296Patch availableCNA
MicrosoftWindows Server 2025 (Server Core installation)10.0.26100.0 to before 10.0.26100.3329610.0.26100.33296Patch availableCNA
  • Windows 11 Version 24H2 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.9168 Fixed in 10.0.26100.9168 Patch available CNA
  • Windows 11 Version 25H2 VendorMicrosoft Affected 10.0.26200.0 to before 10.0.26200.9168 Fixed in 10.0.26200.9168 Patch available CNA
  • Windows 11 version 26H1 VendorMicrosoft Affected 10.0.28000.0 to before 10.0.28000.2704 Fixed in 10.0.28000.2704 Patch available CNA
  • Windows Server 2025 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33296 Fixed in 10.0.26100.33296 Patch available CNA
  • Windows Server 2025 (Server Core installation) VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33296 Fixed in 10.0.26100.33296 Patch available CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*before 10.0.26100.9106VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*before 10.0.26100.9106VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*before 10.0.26200.9106VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*before 10.0.26200.9106VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*before 10.0.28000.2704VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*before 10.0.28000.2704VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:*before 10.0.26100.33222VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26100.9106 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:* Versions before 10.0.26100.9106 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26200.9106 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:* Versions before 10.0.26200.9106 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:* Versions before 10.0.28000.2704 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:* Versions before 10.0.28000.2704 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:* Versions before 10.0.26100.33222 Vulnerable ·Microsoft

Remediation

Microsoft 5 updates

  • KB5121003
    Security Update
    • Windows 11 Version 24H2 for ARM64-based Systems 10.0.26100.9168
    • Windows 11 Version 24H2 for x64-based Systems 10.0.26100.9168
    • Windows 11 Version 25H2 for ARM64-based Systems 10.0.26200.9168
    • Windows 11 Version 25H2 for x64-based Systems 10.0.26200.9168
  • KB5121000
    Security Update
    • Windows 11 Version 26H1 for ARM64-based Systems 10.0.28000.2704
    • Windows 11 version 26H1 for x64-based Systems 10.0.28000.2704
  • KB5120994
    Security Hotpatch Update
    • Windows 11 Version 24H2 for ARM64-based Systems 10.0.26100.9106, 10.0.26200.9106
    • Windows 11 Version 24H2 for x64-based Systems 10.0.26100.9106
    • Windows 11 Version 25H2 for ARM64-based Systems 10.0.26200.9106
    • Windows 11 Version 25H2 for x64-based Systems 10.0.26200.9106
Show 2 more Microsoft updates
  • KB5120233
    Security Update
    • Windows Server 2025 10.0.26100.33296
    • Windows Server 2025 (Server Core installation) 10.0.26100.33296
  • KB5120228
    Security Hotpatch Update
    • Windows Server 2025 10.0.26100.33222
    • Windows Server 2025 (Server Core installation) 10.0.26100.33222

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Spoofing
Exploited
No
Publicly disclosed
No
Exploitability
Exploitation Less Likely

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-56179
  2. 2026-10-03 Alias added: GHSA-rxw5-jh43-59h9

References

Patch 1

  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-73128 Windows Shell Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-17367 MSHTML Framework Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-17364 Windows Shell Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2025-24062 Windows SMB Client Elevation of Privilege Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2025-24042 Internet Shortcut Files Remote Code Execution Vulnerability KEVCVSS 3.1HIGH 8.8
See all 3558 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences