CVE-2026-55031: 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-2026-55031 is a high-severity out-of-bounds read vulnerability (CWE-125) in Microsoft Office Excel as 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 issued an official fix and manages remediation for this cloud service. No active exploitation has been reported.
Potential Impact
Successful exploitation allows an unauthorized attacker to execute code locally with potential full confidentiality, integrity, and availability impact on the affected system. This could lead to significant compromise of user data and system control.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users and administrators should apply the official update as provided in the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55031 to mitigate this vulnerability.
CVE-2026-55031: 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 7.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-55031 is a high-severity out-of-bounds read vulnerability (CWE-125) in Microsoft Office Excel as 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 issued an official fix and manages remediation for this cloud service. No active exploitation has been reported.
Potential Impact
Successful exploitation allows an unauthorized attacker to execute code locally with potential full confidentiality, integrity, and availability impact on the affected system. This could lead to significant compromise of user data and system control.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users and administrators should apply the official update as provided in the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55031 to mitigate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-06-16T14:12:44.285Z
- 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-2026-55031","vendor":"Microsoft"}]
Threat ID: 6a5676b068715ace43f098b9
Added to database: 07/14/2026, 17:49:36 UTC
Last enriched: 08/13/2026, 15:32:08 UTC
Last updated: 08/28/2026, 22:52:12 UTC
Views: 54
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