{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-21261", "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8", "state": "PUBLISHED", "assignerShortName": "microsoft", "dateReserved": "2025-12-11T21:02:05.737Z", "datePublished": "2026-02-10T17:51:37.088Z", "dateUpdated": "2026-02-11T01:15:03.639Z"}, "containers": {"cna": {"title": "Microsoft Excel Information Disclosure Vulnerability", "datePublic": "2026-02-10T08:00:00.000Z", "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_2021:*:*:*:*:ltsc:*:*:*", "versionStartIncluding": "16.0.0.0", "versionEndExcluding": "16.0.10417.20097"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_2019:*:*:*:*:*:*:*:*", "versionStartIncluding": "19.0.0", "versionEndExcluding": "https://aka.ms/OfficeSecurityReleases"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:365_apps:*:*:*:*:enterprise:*:*:*", "versionStartIncluding": "16.0.1", "versionEndExcluding": "https://aka.ms/OfficeSecurityReleases"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_macos_2021:*:*:*:*:*:long_term_servicing_channel:*:*", "versionStartIncluding": "16.0.1", "versionEndExcluding": "16.106.26020821"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_2021:*:*:*:*:long_term_servicing_channel:*:*:*", "versionStartIncluding": "16.0.1", "versionEndExcluding": "https://aka.ms/OfficeSecurityReleases"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_2024:*:*:*:*:long_term_servicing_channel:*:*:*", "versionStartIncluding": "16.0.0", "versionEndExcluding": "https://aka.ms/OfficeSecurityReleases"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_macos_2024:*:*:*:*:*:long_term_servicing_channel:*:*", "versionStartIncluding": "16.0.0", "versionEndExcluding": "16.106.26020821"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:excel_2016:*:*:*:*:*:*:x86:*", "versionStartIncluding": "16.0.0.0", "versionEndExcluding": "16.0.5539.1002"}]}]}], "affected": [{"vendor": "Microsoft", "product": "Office Online Server", "versions": [{"version": "16.0.0.0", "lessThan": "16.0.10417.20097", "versionType": "custom", "status": "affected"}]}, {"vendor": "Microsoft", "product": "Microsoft Office 2019", "platforms": ["32-bit Systems", "x64-based Systems"], "versions": [{"version": "19.0.0", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom", "status": "affected"}]}, {"vendor": "Microsoft", "product": "Microsoft 365 Apps for Enterprise", "platforms": ["32-bit Systems", "x64-based Systems"], "versions": [{"version": "16.0.1", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom", "status": "affected"}]}, {"vendor": "Microsoft", "product": "Microsoft Office LTSC for Mac 2021", "versions": [{"version": "16.0.1", "lessThan": "16.106.26020821", "versionType": "custom", "status": "affected"}]}, {"vendor": "Microsoft", "product": "Microsoft Office LTSC 2021", "platforms": ["x64-based Systems", "32-bit Systems"], "versions": [{"version": "16.0.1", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom", "status": "affected"}]}, {"vendor": "Microsoft", "product": "Microsoft Office LTSC 2024", "platforms": ["32-bit Systems", "x64-based Systems"], "versions": [{"version": "16.0.0", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom", "status": "affected"}]}, {"vendor": "Microsoft", "product": "Microsoft Office LTSC for Mac 2024", "versions": [{"version": "16.0.0", "lessThan": "16.106.26020821", "versionType": "custom", "status": "affected"}]}, {"vendor": "Microsoft", "product": "Microsoft Excel 2016", "platforms": ["32-bit Systems", "x64-based Systems"], "versions": [{"version": "16.0.0.0", "lessThan": "16.0.5539.1002", "versionType": "custom", "status": "affected"}]}], "descriptions": [{"value": "Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.", "lang": "en-US"}], "problemTypes": [{"descriptions": [{"description": "CWE-125: Out-of-bounds Read", "lang": "en-US", "type": "CWE", "cweId": "CWE-125"}]}], "providerMetadata": {"orgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8", "shortName": "microsoft", "dateUpdated": "2026-02-11T01:15:03.639Z"}, "references": [{"name": "Microsoft Excel Information Disclosure Vulnerability", "tags": ["vendor-advisory", "patch"], "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21261"}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en-US", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "baseSeverity": "MEDIUM", "baseScore": 5.5, "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C"}}]}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally."}], "id": "CVE-2026-21261", "lastModified": "2026-02-10T21:51:48.077", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "NONE", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "secure@microsoft.com", "type": "Primary"}]}, "published": "2026-02-10T18:16:28.107", "references": [{"source": "secure@microsoft.com", "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21261"}], "sourceIdentifier": "secure@microsoft.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-125"}], "source": "secure@microsoft.com", "type": "Primary"}]}

{}

{}