CVE-2026-26109: CWE-125: Out-of-bounds Read in Microsoft Microsoft 365 Apps for Enterprise
Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
AI Analysis
Technical Summary
CVE-2026-26109 is a high-severity out-of-bounds read vulnerability (CWE-125) in Microsoft Office Excel, part of Microsoft 365 Apps for Enterprise. It enables an unauthorized attacker to execute code locally by exploiting improper memory access. The vulnerability affects version 16.0.1. Microsoft has released an official fix and manages remediation for this cloud service. No known exploits are reported in the wild at this time.
Potential Impact
Successful exploitation of this vulnerability could allow an unauthorized attacker to execute arbitrary code locally, potentially leading to full compromise of the affected system. The CVSS score of 8.4 reflects high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud service, Microsoft manages remediation server-side. Users and administrators should ensure that their Microsoft 365 Apps for Enterprise environment is updated according to the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26109 to mitigate this vulnerability.
CVE-2026-26109: CWE-125: Out-of-bounds Read in Microsoft Microsoft 365 Apps for Enterprise
Description
Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
CVSS v3.1
Score 8.4high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-26109 is a high-severity out-of-bounds read vulnerability (CWE-125) in Microsoft Office Excel, part of Microsoft 365 Apps for Enterprise. It enables an unauthorized attacker to execute code locally by exploiting improper memory access. The vulnerability affects version 16.0.1. Microsoft has released an official fix and manages remediation for this cloud service. No known exploits are reported in the wild at this time.
Potential Impact
Successful exploitation of this vulnerability could allow an unauthorized attacker to execute arbitrary code locally, potentially leading to full compromise of the affected system. The CVSS score of 8.4 reflects high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud service, Microsoft manages remediation server-side. Users and administrators should ensure that their Microsoft 365 Apps for Enterprise environment is updated according to the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26109 to mitigate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-02-11T15:52:13.910Z
- 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-2026-26109","vendor":"Microsoft"}]
Threat ID: 69b0562fea502d3aa87d6afb
Added to database: 03/10/2026, 17:34:39 UTC
Last enriched: 06/19/2026, 20:30:01 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 215
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