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TI-2026-16970 Aliases CVE-2026-20949GHSA-2vvv-3xfp-234v

Microsoft Excel Security Feature Bypass Vulnerability

Priority LOW 36CWE-284Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from Microsoft.

Summary

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00462 40th percentileScored 2026-11-07
Fix Fixed Microsoft 365 Apps for Enterprise (Microsoft): https://aka.ms/OfficeSecurityReleasesMicrosoft Office LTSC 2021 (Microsoft): https://aka.ms/OfficeSecurityReleases+3 more products

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftMicrosoft 365 Apps for Enterprise16.0.1 to before https://aka.ms/OfficeSecurityReleaseshttps://aka.ms/OfficeSecurityReleasesPatch availableCNA
MicrosoftMicrosoft Office LTSC 202116.0.1 to before https://aka.ms/OfficeSecurityReleaseshttps://aka.ms/OfficeSecurityReleasesPatch availableCNA
MicrosoftMicrosoft Office LTSC 202416.0.0 to before https://aka.ms/OfficeSecurityReleaseshttps://aka.ms/OfficeSecurityReleasesPatch availableCNA
MicrosoftMicrosoft Office LTSC for Mac 202116.0.1 to before 16.105.2601101816.105.26011018Patch availableCNA
MicrosoftMicrosoft Office LTSC for Mac 202416.0.0 to before 16.105.2601101816.105.26011018Patch availableCNA
  • Microsoft 365 Apps for Enterprise VendorMicrosoft Affected 16.0.1 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
  • Microsoft Office LTSC 2021 VendorMicrosoft Affected 16.0.1 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
  • Microsoft Office LTSC 2024 VendorMicrosoft Affected 16.0.0 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
  • Microsoft Office LTSC for Mac 2021 VendorMicrosoft Affected 16.0.1 to before 16.105.26011018 Fixed in 16.105.26011018 Patch available CNA
  • Microsoft Office LTSC for Mac 2024 VendorMicrosoft Affected 16.0.0 to before 16.105.26011018 Fixed in 16.105.26011018 Patch available CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:*2021VulnerableMicrosoft
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:*2021VulnerableMicrosoft
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:*2021VulnerableMicrosoft
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:*2024VulnerableMicrosoft
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:*2024VulnerableMicrosoft
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:*2024VulnerableMicrosoft
  • cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:* Versions 2021 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:* Versions 2021 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:* Versions 2021 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:* Versions 2024 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:* Versions 2024 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:* Versions 2024 Vulnerable ·Microsoft

Remediation

  • Fix · CNA Microsoft 365 Apps for Enterprise (Microsoft) Fixed in https://aka.ms/OfficeSecurityReleases
  • Fix · CNA Microsoft Office LTSC 2021 (Microsoft) Fixed in https://aka.ms/OfficeSecurityReleases
  • Fix · CNA Microsoft Office LTSC 2024 (Microsoft) Fixed in https://aka.ms/OfficeSecurityReleases
  • Fix · CNA Microsoft Office LTSC for Mac 2021 (Microsoft) Fixed in 16.105.26011018
  • Fix · CNA Microsoft Office LTSC for Mac 2024 (Microsoft) Fixed in 16.105.26011018

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Security Feature Bypass
Exploited
No
Publicly disclosed
No
Exploitability
Exploitation Less Likely
ProductStatusPlan or fix
Microsoft 365 Apps for Enterprise for 32-bit SystemsFixed https · //aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 64-bit SystemsFixed https · //aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 32-bit editionsFixed https · //aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 64-bit editionsFixed https · //aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 32-bit editionsFixed https · //aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 64-bit editionsFixed https · //aka.ms/OfficeSecurityReleases
Microsoft Office LTSC for Mac 2021Fixed 16.105.26011018 · Security Update
Microsoft Office LTSC for Mac 2024Fixed 16.105.26011018 · Security Update

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-20949
  2. 2026-10-03 Alias added: GHSA-2vvv-3xfp-234v

References

  • TI-2024-14173 Microsoft Outlook Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-09240 Microsoft Outlook Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-25471 Microsoft Project Remote Code Execution Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2023-17652 Microsoft Outlook Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-17368 Microsoft Word Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 7.8
  • TI-2026-17363 Microsoft Office Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 7.8
See all 935 →

Sources