CVE-2026-55025: CWE-843: Access of Resource Using Incompatible Type ('Type Confusion') in Microsoft Microsoft 365 Apps for Enterprise
Access of resource using incompatible type ('type confusion') in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-55025) is a type confusion issue (CWE-843) in Microsoft Office Excel within Microsoft 365 Apps for Enterprise. It allows unauthorized local code execution due to accessing resources using incompatible types. The CVSS 3.1 vector indicates low attack complexity, no privileges required, user interaction needed, and high impact on confidentiality, integrity, and availability. The vendor has released an official fix and manages remediation for the cloud service.
Potential Impact
Successful exploitation can lead to local code execution by an unauthorized attacker, resulting in full compromise of confidentiality, integrity, and availability of the affected system. The vulnerability is rated high severity with a CVSS score of 7.8.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages the remediation server-side. Users and administrators should follow the guidance in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55025 to ensure their environments are updated and protected.
CVE-2026-55025: CWE-843: Access of Resource Using Incompatible Type ('Type Confusion') in Microsoft Microsoft 365 Apps for Enterprise
Description
Access of resource using incompatible type ('type confusion') 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
This vulnerability (CVE-2026-55025) is a type confusion issue (CWE-843) in Microsoft Office Excel within Microsoft 365 Apps for Enterprise. It allows unauthorized local code execution due to accessing resources using incompatible types. The CVSS 3.1 vector indicates low attack complexity, no privileges required, user interaction needed, and high impact on confidentiality, integrity, and availability. The vendor has released an official fix and manages remediation for the cloud service.
Potential Impact
Successful exploitation can lead to local code execution by an unauthorized attacker, resulting in full compromise of confidentiality, integrity, and availability of the affected system. The vulnerability is rated high severity with a CVSS score of 7.8.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages the remediation server-side. Users and administrators should follow the guidance in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55025 to ensure their environments are updated and protected.
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-2026-55025","vendor":"Microsoft"}]
Threat ID: 6a5676af68715ace43f09885
Added to database: 07/14/2026, 17:49:35 UTC
Last enriched: 07/14/2026, 19:35:38 UTC
Last updated: 07/15/2026, 02:07:28 UTC
Views: 2
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