CVE-2026-88154: CWE-125: Out-of-bounds Read in Microsoft Microsoft 365 Apps for Enterprise
Description
CVE-2026-88154 is an out-of-bounds read vulnerability in Microsoft Office Excel within Microsoft 365 Apps for Enterprise. This flaw allows an unauthorized attacker to disclose information over a network. The vulnerability has a medium severity rating with a CVSS score of 6.5. An official fix is available from Microsoft. The vendor manages remediation for this cloud-hosted service. No known exploits are reported in the wild.
CVSS v3.1
Score 6.5medium
Affected software
Microsoft
Microsoft 365 Apps for Enterprise
Microsoft
Microsoft Office 365 for Mac
Microsoft
Microsoft Office LTSC 2021
Microsoft
Microsoft Office LTSC 2024
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-88154 is a CWE-125 out-of-bounds read vulnerability affecting Microsoft Office Excel in Microsoft 365 Apps for Enterprise. This vulnerability permits an unauthorized attacker to read memory outside the intended bounds, potentially leading to information disclosure over a network. The vulnerability affects specific versions of Microsoft 365 Apps for Enterprise, including =16.0.1, =1.0.0, >=16.0.1 <16.0.14334.20974, and >=16.0.0 <16.0.17932.21056. Microsoft has published an official fix and manages remediation for this cloud service. The CVSS v3.1 score is 6.5, indicating medium severity.
Potential Impact
An attacker can exploit this out-of-bounds read vulnerability to disclose sensitive information over a network without requiring privileges. The impact is limited to confidentiality with no integrity or availability effects reported. No known exploits are currently active in the wild.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users and administrators should ensure their Microsoft 365 Apps for Enterprise installations are updated according to the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88154 to mitigate this issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-09T21:58:19.187Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Is Cloud Service
- true
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88154","vendor":"Microsoft"}]
Threat ID: 6ace85612cdf04f6569ff912
Added to database: 10/13/2026, 19:24:17 UTC
Last enriched: 10/14/2026, 01:33:54 UTC
Last updated: 10/14/2026, 01:33:54 UTC
Views: 3
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