CVE-2026-20949

Improper access control in Microsoft Office Excel allows an unauthorized attacker to bypass a security feature locally.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20949	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:365_apps:-::::enterprise::x64:*
	cpe:2.3:a:microsoft:365_apps:-::::enterprise::x86:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:::::-:x64:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:::::-:x86:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:::::macos::
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:::::-:x64:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:::::-:x86:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:::::macos::

History

No history.

Information

Published : 2026-01-13 18:16

Updated : 2026-01-16 16:20

NVD link : CVE-2026-20949

Mitre link : CVE-2026-20949

CVE.ORG link : CVE-2026-20949

JSON object : View

Products Affected

microsoft

365_apps
office_long_term_servicing_channel

CWE

CWE-284

Improper Access Control

{"id": "CVE-2026-20949", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "secure@microsoft.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "published": "2026-01-13T18:16:22.487", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20949", "tags": ["Vendor Advisory"], "source": "secure@microsoft.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "secure@microsoft.com", "description": [{"lang": "en", "value": "CWE-284"}]}], "descriptions": [{"lang": "en", "value": "Improper access control in Microsoft Office Excel allows an unauthorized attacker to bypass a security feature locally."}], "lastModified": "2026-01-16T16:20:58.787", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*", "vulnerable": true, "matchCriteriaId": "3259EBFE-AE2D-48B8-BE9A-E22BBDB31378"}, {"criteria": "cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*", "vulnerable": true, "matchCriteriaId": "CD25F492-9272-4836-832C-8439EBE64CCF"}, {"criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:*", "vulnerable": true, "matchCriteriaId": "851BAC4E-9965-4F40-9A6C-B73D9004F4C1"}, {"criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:*", "vulnerable": true, "matchCriteriaId": "23B2FA23-76F4-4D83-A718-B8D04D7EA37B"}, {"criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:*", "vulnerable": true, "matchCriteriaId": "BF0E8112-5B6F-4E55-8E40-38ADCF6FC654"}, {"criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:*", "vulnerable": true, "matchCriteriaId": "D31E509A-0B2E-4B41-88C4-0099E800AFE6"}, {"criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:*", "vulnerable": true, "matchCriteriaId": "017A7041-BEF1-4E4E-AC8A-EFC6AFEB01FE"}, {"criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:*", "vulnerable": true, "matchCriteriaId": "EF3E56B5-E6A6-4061-9380-D421E52B9199"}], "operator": "OR"}]}], "sourceIdentifier": "secure@microsoft.com"}