{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-21511", "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8", "state": "PUBLISHED", "assignerShortName": "microsoft", "dateReserved": "2025-12-30T18:10:54.845Z", "datePublished": "2026-02-10T17:51:35.908Z", "dateUpdated": "2026-02-11T01:15:02.257Z"}, "containers": {"cna": {"title": "Microsoft Outlook Spoofing Vulnerability", "datePublic": "2026-02-10T08:00:00.000Z", "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:sharepoint_server_2016:*:*:*:*:enterprise:*:*:*", "versionStartIncluding": "16.0.0", "versionEndExcluding": "16.0.5539.1002"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:sharepoint_server_2019:*:*:*:*:*:*:*:*", "versionStartIncluding": "16.0.0", "versionEndExcluding": "16.0.10417.20097"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_2019:*:*:*:*:*:*:*:*", "versionStartIncluding": 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[{"description": "CWE-502: Deserialization of Untrusted Data", "lang": "en-US", "type": "CWE", "cweId": "CWE-502"}]}], "providerMetadata": {"orgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8", "shortName": "microsoft", "dateUpdated": "2026-02-11T01:15:02.257Z"}, "references": [{"name": "Microsoft Outlook Spoofing Vulnerability", "tags": ["vendor-advisory", "patch"], "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21511"}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en-US", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "baseSeverity": "HIGH", "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": "Deserialization of untrusted data in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network."}], "id": "CVE-2026-21511", "lastModified": "2026-02-10T21:51:48.077", "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": "2026-02-10T18:16:33.337", "references": [{"source": "secure@microsoft.com", "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21511"}], "sourceIdentifier": "secure@microsoft.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-502"}], "source": "secure@microsoft.com", "type": "Primary"}]}

{}

{}