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TI-2026-39696 Aliases CVE-2026-54988GHSA-cpg5-9rxq-hxph

Microsoft Excel Information Disclosure Vulnerability

Priority LOW 28CWE-125Published · Updated

Key facts

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

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

Summary

Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00461 40th percentileScored 2026-11-07
Fix Fixed Microsoft: 2 updates

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

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 Excel 201616.0.0.0 to before 16.0.5561.100116.0.5561.1001Patch availableCNA
MicrosoftMicrosoft Office 201919.0.0 to before https://aka.ms/OfficeSecurityReleaseshttps://aka.ms/OfficeSecurityReleasesPatch availableCNA
MicrosoftMicrosoft Office 365 for Mac1.0.0 to before 16.111.2607121516.111.26071215Patch 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 16.111.2607121516.111.26071215Patch availableCNA
MicrosoftMicrosoft Office LTSC for Mac 202416.0.0 to before 16.111.2607121516.111.26071215Patch availableCNA
MicrosoftOffice Online Server16.0.0.0 to before 16.0.10417.2017516.0.10417.20175Patch 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 Excel 2016 VendorMicrosoft Affected 16.0.0.0 to before 16.0.5561.1001 Fixed in 16.0.5561.1001 Patch available CNA
  • Microsoft Office 2019 VendorMicrosoft Affected 19.0.0 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
  • Microsoft Office 365 for Mac VendorMicrosoft Affected 1.0.0 to before 16.111.26071215 Fixed in 16.111.26071215 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 16.111.26071215 Fixed in 16.111.26071215 Patch available CNA
  • Microsoft Office LTSC for Mac 2024 VendorMicrosoft Affected 16.0.0 to before 16.111.26071215 Fixed in 16.111.26071215 Patch available CNA
  • Office Online Server VendorMicrosoft Affected 16.0.0.0 to before 16.0.10417.20175 Fixed in 16.0.10417.20175 Patch available CNA

CPE configurations NVD · 14

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:excel:2016:*:*:*:*:*:x64:*2016VulnerableMicrosoft
cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x86:*2016VulnerableMicrosoft
cpe:2.3:a:microsoft:microsoft_365:-:*:*:*:*:macos:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x64:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x86:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:macos:-:*not specified by NVDVulnerableMicrosoft
  • 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:excel:2016:*:*:*:*:*:x64:* Versions 2016 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x86:* Versions 2016 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:microsoft_365:-:*:*:*:*:macos:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x64:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x86:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:macos:-:* Versions not specified by NVD Vulnerable ·Microsoft
Show 4 more CPE
CPEVersionsRoleVendor
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:macos:-:*not specified by NVDVulnerableMicrosoft
cpe:2.3:a:microsoft:office_online_server:*:*:*:*:*:*:*:*before 16.0.10417.20175VulnerableMicrosoft
  • cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:macos:-:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:office_online_server:*:*:*:*:*:*:*:* Versions before 16.0.10417.20175 Vulnerable ·Microsoft

Remediation

Microsoft 2 updates

  • Security Update
    • Office Online Server 16.0.10417.20175
  • Security Update
    • Microsoft Excel 2016 (32-bit edition) 16.0.5556.1001, 16.0.5561.1001
    • Microsoft Excel 2016 (64-bit edition) 16.0.5556.1001, 16.0.5561.1001

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Information Disclosure
Exploited
No
Publicly disclosed
No
Exploitability
Exploitation Unlikely
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 2019 for 32-bit editionsFixed https · //aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 64-bit editionsFixed https · //aka.ms/OfficeSecurityReleases
Microsoft Office 365 for MacFixed 16.111.26071215 · Security Update
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 16.111.26071215 · Security Update
Microsoft Office LTSC for Mac 2024Fixed 16.111.26071215 · Security Update

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-54988
  2. 2026-10-03 Alias added: GHSA-cpg5-9rxq-hxph

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