{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-40406", "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8", "state": "PUBLISHED", "assignerShortName": "microsoft", "dateReserved": "2026-04-13T00:27:50.798Z", "datePublished": "2026-05-12T16:58:43.279Z", "dateUpdated": "2026-05-12T17:53:42.476Z"}, "containers": {"cna": {"title": "Windows TCP/IP Information Disclosure Vulnerability", "datePublic": "2026-05-12T14:00:00.000Z", "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*", "versionStartIncluding": "10.0.17763.0", "versionEndExcluding": "10.0.17763.8755"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*", "versionStartIncluding": "10.0.17763.0", "versionEndExcluding": "10.0.17763.8755"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*", 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"baseScore": 7.5, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C"}}]}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "Use after free in Windows TCP/IP allows an unauthorized attacker to disclose information over a network."}], "id": "CVE-2026-40406", "lastModified": "2026-05-12T18:17:18.430", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "secure@microsoft.com", "type": "Primary"}]}, "published": "2026-05-12T18:17:18.430", "references": [{"source": "secure@microsoft.com", "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40406"}], "sourceIdentifier": "secure@microsoft.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "secure@microsoft.com", "type": "Primary"}]}

{}

{"created": "2026-05-12T20:15:24.320989+00:00", "updated": "2026-05-12T20:15:24.320999+00:00", "vendors": []}