CVE-2026-56181 (GCVE-0-2026-56181)

Vulnerability from cvelistv5 – Published: 2026-07-14 17:10 – Updated: 2026-07-14 19:42
VLAI
Title
Windows Network Address Translation (NAT) Spoofing Vulnerability
Summary
Origin validation error in Windows Network Address Translation (NAT) allows an unauthorized attacker to perform spoofing over an adjacent network.
Severity
8.3 (High)
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
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-346 - Origin Validation Error
Assigner
References
Impacted products
Vendor Product Version
Microsoft Windows 11 Version 24H2 Affected: 10.0.26100.0 , < 10.0.26100.8875 (custom)
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Microsoft Windows 11 Version 25H2 Affected: 10.0.26200.0 , < 10.0.26100.8875 (custom)
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Microsoft Windows 11 version 26H1 Affected: 10.0.28000.0 , < 10.0.28000.2525 (custom)
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Microsoft Windows Server 2025 Affected: 10.0.26100.0 , < 10.0.26100.33158 (custom)
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Microsoft Windows Server 2025 (Server Core installation) Affected: 10.0.26100.0 , < 10.0.26100.33158 (custom)
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Date Public
2026-07-14 14:00
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.