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TI-2026-72975 Aliases CVE-2026-88195GHSA-3f28-q268-hccq

Buffer over-read in Microsoft Office Excel leaks information

Priority LOW 30CWE-126Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-126 and the CVSS impact.

Summary

Microsoft Office LTSC 2021 from 16.0.1 before 16.0.14334.20974, Microsoft Office LTSC 2024 from 16.0.0 before 16.0.17932.21056, and Microsoft 365 Apps for Enterprise from 16.0.1 are affected. A buffer over-read (CWE-126) in Microsoft Office Excel lets the software read past the end of a buffer. An unauthenticated remote attacker can disclose information, and the attack requires a user to take an action.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Buffer over-read in Microsoft Office Excel allows an unauthorized attacker to disclose information over a network.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00809 57th percentileScored 2026-11-07
Fix Fixed Microsoft 365 Apps for Enterprise (Microsoft): https://aka.ms/OfficeSecurityReleasesMicrosoft Office LTSC 2021 (Microsoft): 16.0.14334.20974+1 more product

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 Office LTSC 202116.0.1 to before 16.0.14334.2097416.0.14334.20974Patch availableCNA
MicrosoftMicrosoft Office LTSC 202416.0.0 to before 16.0.17932.2105616.0.17932.21056Patch 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 16.0.14334.20974 Fixed in 16.0.14334.20974 Patch available CNA
  • Microsoft Office LTSC 2024 VendorMicrosoft Affected 16.0.0 to before 16.0.17932.21056 Fixed in 16.0.17932.21056 Patch available CNA

CPE configurations NVD · 6

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_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_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: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_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_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

Remediation

Microsoft Office LTSC 2021 is fixed in 16.0.14334.20974 and Microsoft Office LTSC 2024 is fixed in 16.0.17932.21056. Microsoft 365 Apps for Enterprise is fixed in the updates listed on the Microsoft Office security releases page.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Microsoft 365 Apps for Enterprise (Microsoft) Fixed in https://aka.ms/OfficeSecurityReleases
  • Fix · CNA Microsoft Office LTSC 2021 (Microsoft) Fixed in 16.0.14334.20974
  • Fix · CNA Microsoft Office LTSC 2024 (Microsoft) Fixed in 16.0.17932.21056

Timeline

  1. 2026-10-13 Threatist record created from CVE-2026-88195
  2. 2026-10-13 Alias added: GHSA-3f28-q268-hccq
  3. 2026-10-25 EPSS moved to the 50th–90th percentile

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