Medium MSRC-CVE-2026-56179 1 CVE

Windows Network Address Translation (NAT) Spoofing Vulnerability

Published Aug 11, 2026 · Updated Aug 11, 2026

Vendor: Microsoft

Summary

Impact: Spoofing. Microsoft rating: Moderate. Not known to be exploited — Exploitation Less Likely. Customer action: Required.

Details

Security updates
10.0.26100.33296 — https://support.microsoft.com/help/5120233
10.0.26100.33222 — https://support.microsoft.com/help/5120228
10.0.26200.9168 — https://support.microsoft.com/help/5121003
10.0.26200.9106 — https://support.microsoft.com/help/5120994
10.0.28000.2704 — https://support.microsoft.com/help/5121000

Vulnerabilities 1

High 8.3

CVE-2026-56179

Windows Network Address Translation (NAT) Spoofing Vulnerability

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

Microsoft Windows Server 2025 Windows Server 2025 (Server Core installation) Windows 11 Version 24H2 Windows

Aug 11, 2026

Revision history

2026-08-11 #1
Information published.

References

CVE-2026-56179 Windows Network Address Translation (NAT) Spoofing Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56179
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
Common Vulnerability Scoring System
https://www.first.org/cvss