{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-55899", "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8", "state": "PUBLISHED", "assignerShortName": "microsoft", "dateReserved": "2026-06-17T17:36:34.621Z", "datePublished": "2026-07-14T17:05:10.091Z", "dateUpdated": "2026-07-14T19:37:18.403Z"}, "containers": {"cna": {"title": "Microsoft Excel Remote Code Execution Vulnerability", "datePublic": "2026-07-14T14:00:00.000Z", "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_365:*:*:*:*:*:macos:*:*", "versionStartIncluding": "1.0.0", "versionEndExcluding": "16.111.26071215"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_2021:*:*:*:*:ltsc:*:*:*", "versionStartIncluding": "16.0.0.0", "versionEndExcluding": "16.0.10417.20175"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_2019:*:*:*:*:*:*:*:*", "versionStartIncluding": "19.0.0", 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"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55899"}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en-US", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "baseSeverity": "HIGH", "baseScore": 7.8, "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C"}}]}}}

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