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TI-2021-17518 Aliases CVE-2021-40471GHSA-5fv8-8523-rqc9

Microsoft Excel Remote Code Execution Vulnerability

Priority LOW 38Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Microsoft Excel Remote Code Execution Vulnerability

Why it matters now

EPSS 0.02302 83rd percentileScored 2026-11-07
Fix Fixed Microsoft Office 2019 (Microsoft): https://aka.ms/OfficeSecurityReleasesMicrosoft 365 Apps for Enterprise (Microsoft): https://aka.ms/OfficeSecurityReleases+3 more products

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftMicrosoft Office 201919.0.0 to before https://aka.ms/OfficeSecurityReleaseshttps://aka.ms/OfficeSecurityReleasesPatch availableCNA
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 201616.0.0 to before 16.0.5227.100016.0.5227.1000Patch availableCNA
MicrosoftMicrosoft Office 2013 Service Pack 115.0.0 to before 15.0.5389.100015.0.5389.1000Patch availableCNA
  • Microsoft Office 2019 VendorMicrosoft Affected 19.0.0 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
  • 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 2016 VendorMicrosoft Affected 16.0.0 to before 16.0.5227.1000 Fixed in 16.0.5227.1000 Patch available CNA
  • Microsoft Office 2013 Service Pack 1 VendorMicrosoft Affected 15.0.0 to before 15.0.5389.1000 Fixed in 15.0.5389.1000 Patch available CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office:2013:sp1:*:*:*:*:*:*2013 sp1VulnerableMicrosoft
cpe:2.3:a:microsoft:office:2013:sp1:*:*:rt:*:*:*2013 sp1VulnerableMicrosoft
cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:*:*2016VulnerableMicrosoft
cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:*:*2019VulnerableMicrosoft
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:*:*:*2021VulnerableMicrosoft
  • cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office:2013:sp1:*:*:*:*:*:* Versions 2013 sp1 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office:2013:sp1:*:*:rt:*:*:* Versions 2013 sp1 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:*:* Versions 2016 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:*:* Versions 2019 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:*:*:* Versions 2021 Vulnerable ·Microsoft

Remediation

  • Fix · CNA Microsoft Office 2019 (Microsoft) Fixed in https://aka.ms/OfficeSecurityReleases
  • 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 2016 (Microsoft) Fixed in 16.0.5227.1000
  • Fix · CNA Microsoft Office 2013 Service Pack 1 (Microsoft) Fixed in 15.0.5389.1000

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-40471
  2. 2026-10-03 Alias added: GHSA-5fv8-8523-rqc9

References

Patch 1

  • 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

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences