High severity8.3NVD Advisory· Published Jul 14, 2026· Updated Jul 22, 2026

CVE-2026-56181

Description

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

Microsoft/Windows Network Address Translation (NAT)llm-fuzzy
Microsoft/Windows 11 24h2
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:*
Range: <10.0.26100.8875
Microsoft/Windows 11 25h2
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:*:*
Range: <10.0.26200.8875
Microsoft/Windows 11 26h1
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:*:*
Range: <10.0.28000.2525
Microsoft/Windows Server 2025
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*
Range: <10.0.26100.33158