CVE-2026-55058: 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-2026-55058 is a CWE-125 out-of-bounds read vulnerability 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 of the product. Microsoft has published 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 lead to local code execution with high impact on confidentiality, integrity, and availability. This means an attacker could run arbitrary code on the affected system, potentially leading to full compromise of the local environment.
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 follow the guidance in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55058 to ensure their environments are updated and protected.
CVE-2026-55058: 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-2026-55058 is a CWE-125 out-of-bounds read vulnerability 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 of the product. Microsoft has published 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 lead to local code execution with high impact on confidentiality, integrity, and availability. This means an attacker could run arbitrary code on the affected system, potentially leading to full compromise of the local environment.
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 follow the guidance in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55058 to ensure their environments are updated and protected.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-06-16T14:13:49.836Z
- 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-2026-55058","vendor":"Microsoft"}]
Threat ID: 6a5676b568715ace43f0aafb
Added to database: 07/14/2026, 17:49:41 UTC
Last enriched: 07/14/2026, 19:19:12 UTC
Last updated: 07/15/2026, 01:27:25 UTC
Views: 2
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